D&D 3.5 had tons and tons of tables for generating treasure on-the-fly. So many, in fact, that I often became overwhelmed at the complexity.
The 4th Edition D&D simplifies it to one table. You use a single d10 roll, and it gives you generic distributions of treasure. Too simple for my tastes.
So, here's a single-sheet PDF of Random Treasure for D&D 4E
You still need only a single d10 die roll, but this will give you something specific (a ring or a pearl) instead of a generic description (art object or gem). It's also condensed down to one page, so you can easily refer to it while playing.