Invoking SysRq functions over serial line

A few weeks ago, I saw one of my co-worker let the kernel reboot from minicom with some key combination(Ctrl-a + f + b) ,and then he explained me shortly, he did it because he wanted to save really small time, instead of typing "reboot[RETURN]"(just 7 key press!!) or powering down/up the targets(plug and unplug, just 2 actions!!). I thought he was enough lazy to be a hacker:) Later I found that it just sent SysRq and this feature was quite comfortable when development. Though I've been using minicom relatively for a long time, I've never used this feature;;^^). This also can make kernel reboot, show memory status, show task lists, halt, sync, invoke oom manually, and so on. When you don't remember key sequence, plase press "Ctrl-a + f + h" for [HELP]. Finally, I've got to like it so much:)
http://ozlabs.org/pipermail/linuxppc-embedded/2002-October/008788.html

PS. I guess, this invoking oom killer may be useful to distinguish the real lockup from the heavy memory pressure, simply.