i hate to burst your bubble, but.... one copy purchased means one copy installed AT ANY TIME... technically, you are running an illegal copy of photoshop on your computer. if it were legal for groups of people to purchase just one copy, an entire company could purchase just one copy, and put it on as many machines as they feel like... (well, there are certain agreements that allow that, but those are called 'per seat' agreements, which doesn't work with the retail, boxed copy of photoshop.) you might want to spend some time reading the license agreement. if you are in doubt, call adobe and ask. they will be happy to explain it to you... i think they've a 1-800 number.