diff --git a/cache.h b/cache.h
index bf468e52352c193b355222b718d9f5125c26052c..04ae824d64ec8e3adf26c3afeeae2c1a0e8ccd3d 100644
--- a/cache.h
+++ b/cache.h
@@ -747,7 +747,8 @@ const char *show_date_relative(unsigned long time, int tz,
 			       size_t timebuf_size);
 int parse_date(const char *date, char *buf, int bufsize);
 void datestamp(char *buf, int bufsize);
-unsigned long approxidate(const char *);
+#define approxidate(s) approxidate_careful((s), NULL)
+unsigned long approxidate_careful(const char *, int *);
 unsigned long approxidate_relative(const char *date, const struct timeval *now);
 enum date_mode parse_date_format(const char *format);
 
diff --git a/date.c b/date.c
index 5d05ef61cfb140f004702a5ed614afa755c50670..17385a9b62abf17868403b0df40155c19efa3515 100644
--- a/date.c
+++ b/date.c
@@ -696,6 +696,11 @@ static unsigned long update_tm(struct tm *tm, struct tm *now, unsigned long sec)
 	return n;
 }
 
+static void date_now(struct tm *tm, struct tm *now, int *num)
+{
+	update_tm(tm, now, 0);
+}
+
 static void date_yesterday(struct tm *tm, struct tm *now, int *num)
 {
 	update_tm(tm, now, 24*60*60);
@@ -770,6 +775,7 @@ static const struct special {
 	{ "PM", date_pm },
 	{ "AM", date_am },
 	{ "never", date_never },
+	{ "now", date_now },
 	{ NULL }
 };
 
@@ -790,7 +796,7 @@ static const struct typelen {
 	{ NULL }
 };
 
-static const char *approxidate_alpha(const char *date, struct tm *tm, struct tm *now, int *num)
+static const char *approxidate_alpha(const char *date, struct tm *tm, struct tm *now, int *num, int *touched)
 {
 	const struct typelen *tl;
 	const struct special *s;
@@ -804,6 +810,7 @@ static const char *approxidate_alpha(const char *date, struct tm *tm, struct tm
 		int match = match_string(date, month_names[i]);
 		if (match >= 3) {
 			tm->tm_mon = i;
+			*touched = 1;
 			return end;
 		}
 	}
@@ -812,6 +819,7 @@ static const char *approxidate_alpha(const char *date, struct tm *tm, struct tm
 		int len = strlen(s->name);
 		if (match_string(date, s->name) == len) {
 			s->fn(tm, now, num);
+			*touched = 1;
 			return end;
 		}
 	}
@@ -821,11 +829,14 @@ static const char *approxidate_alpha(const char *date, struct tm *tm, struct tm
 			int len = strlen(number_name[i]);
 			if (match_string(date, number_name[i]) == len) {
 				*num = i;
+				*touched = 1;
 				return end;
 			}
 		}
-		if (match_string(date, "last") == 4)
+		if (match_string(date, "last") == 4) {
 			*num = 1;
+			*touched = 1;
+		}
 		return end;
 	}
 
@@ -835,6 +846,7 @@ static const char *approxidate_alpha(const char *date, struct tm *tm, struct tm
 		if (match_string(date, tl->type) >= len-1) {
 			update_tm(tm, now, tl->length * *num);
 			*num = 0;
+			*touched = 1;
 			return end;
 		}
 		tl++;
@@ -852,6 +864,7 @@ static const char *approxidate_alpha(const char *date, struct tm *tm, struct tm
 			diff += 7*n;
 
 			update_tm(tm, now, diff * 24 * 60 * 60);
+			*touched = 1;
 			return end;
 		}
 	}
@@ -866,6 +879,7 @@ static const char *approxidate_alpha(const char *date, struct tm *tm, struct tm
 			tm->tm_year--;
 		}
 		tm->tm_mon = n;
+		*touched = 1;
 		return end;
 	}
 
@@ -873,6 +887,7 @@ static const char *approxidate_alpha(const char *date, struct tm *tm, struct tm
 		update_tm(tm, now, 0); /* fill in date fields if needed */
 		tm->tm_year -= *num;
 		*num = 0;
+		*touched = 1;
 		return end;
 	}
 
@@ -929,9 +944,12 @@ static void pending_number(struct tm *tm, int *num)
 	}
 }
 
-static unsigned long approxidate_str(const char *date, const struct timeval *tv)
+static unsigned long approxidate_str(const char *date,
+				     const struct timeval *tv,
+				     int *error_ret)
 {
 	int number = 0;
+	int touched = 0;
 	struct tm tm, now;
 	time_t time_sec;
 
@@ -951,33 +969,42 @@ static unsigned long approxidate_str(const char *date, const struct timeval *tv)
 		if (isdigit(c)) {
 			pending_number(&tm, &number);
 			date = approxidate_digit(date-1, &tm, &number);
+			touched = 1;
 			continue;
 		}
 		if (isalpha(c))
-			date = approxidate_alpha(date-1, &tm, &now, &number);
+			date = approxidate_alpha(date-1, &tm, &now, &number, &touched);
 	}
 	pending_number(&tm, &number);
+	if (!touched)
+		*error_ret = 1;
 	return update_tm(&tm, &now, 0);
 }
 
 unsigned long approxidate_relative(const char *date, const struct timeval *tv)
 {
 	char buffer[50];
+	int errors = 0;
 
 	if (parse_date(date, buffer, sizeof(buffer)) > 0)
 		return strtoul(buffer, NULL, 0);
 
-	return approxidate_str(date, tv);
+	return approxidate_str(date, tv, &errors);
 }
 
-unsigned long approxidate(const char *date)
+unsigned long approxidate_careful(const char *date, int *error_ret)
 {
 	struct timeval tv;
 	char buffer[50];
+	int dummy = 0;
+	if (!error_ret)
+		error_ret = &dummy;
 
-	if (parse_date(date, buffer, sizeof(buffer)) > 0)
+	if (parse_date(date, buffer, sizeof(buffer)) > 0) {
+		*error_ret = 0;
 		return strtoul(buffer, NULL, 0);
+	}
 
 	gettimeofday(&tv, NULL);
-	return approxidate_str(date, &tv);
+	return approxidate_str(date, &tv, error_ret);
 }
diff --git a/sha1_name.c b/sha1_name.c
index 44bb62d270739a232e87c90c05ce89fcc86bc15b..04fb3b8fed2970bf7fde83e0dc38cea9485ca3d2 100644
--- a/sha1_name.c
+++ b/sha1_name.c
@@ -395,9 +395,12 @@ static int get_sha1_basic(const char *str, int len, unsigned char *sha1)
 		} else if (0 <= nth)
 			at_time = 0;
 		else {
+			int errors = 0;
 			char *tmp = xstrndup(str + at + 2, reflog_len);
-			at_time = approxidate(tmp);
+			at_time = approxidate_careful(tmp, &errors);
 			free(tmp);
+			if (errors)
+				return -1;
 		}
 		if (read_ref_at(real_ref, at_time, nth, sha1, NULL,
 				&co_time, &co_tz, &co_cnt)) {
diff --git a/t/t0101-at-syntax.sh b/t/t0101-at-syntax.sh
new file mode 100755
index 0000000000000000000000000000000000000000..5e298c510259c54650cb0d0f3f3155ac48094ccb
--- /dev/null
+++ b/t/t0101-at-syntax.sh
@@ -0,0 +1,45 @@
+#!/bin/sh
+
+test_description='various @{whatever} syntax tests'
+. ./test-lib.sh
+
+test_expect_success 'setup' '
+	test_commit one &&
+	test_commit two
+'
+
+check_at() {
+	echo "$2" >expect &&
+	git log -1 --format=%s "$1" >actual &&
+	test_cmp expect actual
+}
+
+test_expect_success '@{0} shows current' '
+	check_at @{0} two
+'
+
+test_expect_success '@{1} shows old' '
+	check_at @{1} one
+'
+
+test_expect_success '@{now} shows current' '
+	check_at @{now} two
+'
+
+test_expect_success '@{2001-09-17} (before the first commit) shows old' '
+	check_at @{2001-09-17} one
+'
+
+test_expect_success 'silly approxidates work' '
+	check_at @{3.hot.dogs.and.30.years.ago} one
+'
+
+test_expect_success 'notice misspelled upstream' '
+	test_must_fail git log -1 --format=%s @{usptream}
+'
+
+test_expect_success 'complain about total nonsense' '
+	test_must_fail git log -1 --format=%s @{utter.bogosity}
+'
+
+test_done