Free Icon Maker

[Capp]

Hey everyone,
Does anybody know of a good free or relatively cheap piece of software that you can use to make icons. I would like to be able to make better looking XP-ish kind of icons without just buying a sheet of pre-made from some site.

I have trialed a few that are free for 30 days, but they all WaterMark the icons so you can't actually use them. I'd prefer a free or open source method, if available.

Thanks,

Andy