Here are a few:
-Next to your item in the CPU, Ram, HD spots. have the unequip link after it. That way you dont have to go searching for it when you buy a new one.
-Sort your list by groups, for me it goes CPU, ram, hard drive, board, HD,HD,HD,HD
-Have another column in your inventory to sell from, maybe have a popup saying are you sure you want to sell your X for 1000 cds
Simple and easy to implemnt