The War Gamers League mod did the a time-fused greanade thing
Can't remeber, but I'm sure they just stoped moving when they hit the ground, waited a few seconds, then blow up
That could be modded with setvelocity to make it roll..?
De-PBOed the files, and couldn't seem to find the script, though
Hold on, search the forum, there was a script that did exactly that, in the beta testing section, maybe?
- Ben