If you don't know what to buy exactly then face it... you probably don't want either badly enough to not make it a piece of electronic junk lying around your house after a while.

But if you open up a bank account and put all the toy money you can grab off your parents in to it whenever you get the chance... after a while you'll be able to afford a toy of a much higher price-class than that of whatever you can buy with the usual "that time" money. Look at the bright side... if you find something else you really like tomorrow you can always go and get it then!

I'll be honest with you... most people lack the self-discipline to do something like that... that's why electronics companies and such exist this long! lol