I, too, will try to sell GURPS.
Retreater said:
Basically what's I'm looking for is (in no particular order):
1. Something that's in print; I don't want a PDF rule book
Check.
2. More or less rules-lite (in comparison to D&D 3.5)
The basics of the GURPS rule system are quire simple. You can download
GURPS Lite, a 32-page condensed version of the GURPS system, for free.
It only covers playing mundane humans without supernatural powers, but that in itself still covers a wide range of people from throughout history. The GURPS Basic Set has a lot more detail - but most of that is optional and not needed for most campaigns.
3. Something that would be affordable to get started with (don't want to have to buy a lot of books, just in case it doesn't catch on with my group)
Well, GURPS Lite is free. I suggest running a horror adventure set in the modern day or a historical period with it - if the PCs don't have supernatural powers, this will be entirely sufficient.
The two books of the Basic Set do require some more investment, but it's a reasonable amount - and these two books cover a far wider range of genres than D&D.
Not required, though if you want to use them, GURPS covers that too.
5. A system that can accomodate different genres (the pure fantasy of D&D is getting old)
That's where GURPS shines - it can cover pretty much any genre you can imagine, and does gritty and cinematic equally well. The only genre where I have my doubts about GURPS 4E is a campaign with characters of truly cosmic powers (like when they are actual gods), but anything apart from that is doable.
And like others have said,
a large number of GURPS 3E worldbooks are available for $10 apiece at the moment - a great price for almost all of them. Most can be converted to GURPS 4E with a minimum of effort.