Your character can hold infinitely more than his maximum
carry weight by trading with someone. The game doesn't check to
see if you can carry what you are buying. For example, a character
can have the minigun, the flame thrower, rocket launcher, plasma
rifle, .233 pistol, as well as lots of heavy ammo. If you have
a problem where you need to pick something up from the game world,
you can give everything except your money and other light things
to Ian, then pick up the item. You can get all your items back,
thanks to both the "Barter" and "Weight" glitches.
Unfortunately the NPC fails to realize that the items are yours
and that you just gave them to him to hold.
Strategy
Strategy: by Cole Simmons
Strategy: by Igor Lowicki