yea nerf guns are user-friendly cause of the foam they use. and well i don't think any office would survive a paintball (or not even airsoft) fight
we've done laser tag with friends a couple of times, it's surprising how one 20-minute game can make you exhausted while you're not even allowed to run (we do the indoor one with mazes and stuff).
and now that i think of it, i guess the term "to get nerfed" is derived from the same thing - a soft foamy substance that doesn't hurt you