I'm trying to decide what kind of protection scheme to use against casual copying for my game, and a dated-based key keeps bugging me.

It seems that its a trend among softwares/sharewares that use date-based serials to sell number of installations. take Windows XP or 3d studio max that allow up to specific number of installations.

While its a good measure of defense against multiple installations by the same user (i.e. casual copy piracy), it might despair those who do need to reinstall their game through the years.

and then there's the databse you need to keep track of those who bought the game and want new serial-key. which can be done by an automated program, or by yourself (putting even more work by emailing).

It seems like much work when all you want is to sell the game and get it over with. not that i mind giving support, but i'm afraid of the volume of the "give me new serial" requests.

I thought about "declaring" like many, that i'm allowing a specific number of installations.

does anyone has experience with this kind of method?

I'd also be glad to hear about experience with date-based keys.