How to recall system reboot history

One easy way to get some reboot history of a system is running the following script :

for wtmp in `ls -t /var/log/wtmp*`; do last reboot -f $wtmp; done

Here is an example of it :

xxx:~ # for wtmp in `ls -t /var/log/wtmp*`; do last reboot -f $wtmp; done
reboot system boot 2.6.16.60-0.21-s Sun Apr 19 23:43 (3+11:51)
reboot system boot 2.6.16.60-0.21-s Fri Apr 17 11:38 (2+11:41)
reboot system boot 2.6.16.60-0.21-s Thu Apr 16 12:28 (21:19)
reboot system boot 2.6.16.60-0.21-s Thu Apr 16 11:01 (00:-32)

wtmp begins Thu Apr 16 11:01:27 2009
xxx:~ #