Still playing Fallout 3 every night to pass the time. I hit upon a good amount of ammo for my sniper rifle (oh how I do love my sniper rifle but ammo for it is hard to come by).
I went to Minefield and made it to the playground, as the quest directed, and was shot at - so of course I shot back. I headshotted the guy (I've got my small guns stats way high - sneak and small guns are my favorite stats), who was up high in an open building, with most walls blasted away. And at first I wasn't going to bother climbing up to loot the body, but then I kept attempting and failing to collect a mine in the area for the quest giver (they kept exploding on me), so I had worked my way around to the stairs and said what the hey, climbed up and hot damn if there weren't four ammunition boxes by the body, plus he had a sniper rifle too.
I was able to repair my sniper rifle (first time I got to do that myself!) and packed up a few rounds. I still have to use it sparingly, as I have less than 30 shots if I recall correctly.
I've been tempted to use the "unlimited ammo" cheat, but I do so enjoy the tension and urgency, having to choose between weapons, the fear when I've run out of ammo for my assault rifle - my mainstay weapon - and have to resort to my combat shotgun. The shotgun surely packs a wallop, but when multiple enemies are bearing down on you, it can be impossible to kill them before they kill you.
So I do have my weapon preferences in the game, and of course I deplete their respective ammo most quickly.
The scarcity provides a definite fun-stress factor to the game that simply would not be there if ammo was unlimited. Turning a corner into three or four super-mutants when you're down to a handful of bullets can make your fight or flight response really ramp up.
My only real gripe is the continued crashes; everything else about the game is just fine, just what I would expect out of a shooter RPG. But crashes. Ugh. All my updates are done, yet every hour or so it will crash. Fortunately the auto-save upon entering/exiting buildings saves me from terrible setbacks, and I have taken to saving every so often when I'm out wandering the open areas.
Fight the good fight!