This tends to be a rather obvious but shockingly enough rarely used tip:
Say your in Coop and your buddy is hurting bad, you got the enemies cleared out
and there ain't no health to be seen, what's a good friend to do??
Why, put them out of their misery! Find a nice quiet spot and blast your friend
to kingdom-come. Back up a few inches and resurrect your friend and allow him to
grab his dropped gear and continue on. If your the mean type however, feel free
to steal his stuff right out from under him (You know you want those shotgun
rounds) and just pass it off as "Oops! My mistake", but beware of
retaliation.
This also works well if your low on Ammo, like Assault Rifle Ammo (is that
possible in this game? That stuff's everywhere) just shot yer'self up and your resurrected
body will
bring back a shiny new AR with some Ammo. Grab what you had left over and voila,
more ammo for you!