DescentBB

found these in the temp directory of an XP machine. Do they mean anything in particular?

~tmp1337.exe
~dos1337.exe
~cln1337.exe (edited - not "cls")

hacker crap? windows stupid? other?

All I know is they must be leet.

I'd put it to a heavy duty scanner and see what turns up. I'm suspicious.....

after dumping them in the recycle bin, I ran a hijackthis scan that didn't seem to show up anything terrible. But I'm no expert there.

Hijack this doesn't really do anything for cases like these, scan them with microsoft security essentials or any other full antivirus scanner (malwarebytes might also work).

this box get a regular scan with Mcafee AV+, which hasn't shown anything bad to date. mbam showed no issues.

if I try any other scan tools, can I just leave the files in the recycle bin, or do I have to put them back in the temp directory?

First guess is that it's malicious crap.

Or, perhaps the user named them that herself, she codes, and they are custom compiled programs, the programming environment putting them into the temp folder.

Upload the files to one of those sites that will scan the file with 30 different antivirus scanners.