Oh Wow. Five Indie Games, Pay What You Want.

I sadly don't have time just now to go in-depth and explain why these games are great - well, I know why four of them are great, I haven't actually played Penumbra - but right now a crew of excellent indie developers have teamed up with Wolfire Games to offer their extremely popular and well received games (World of Goo, Gish, Aquaria, Lugaru HD, and Penumbra) in a bundle for whatever price you want to pay, in the Humble Indie Bundle.

Better than that, you can decide exactly where the money goes.  Give some of it to each developer, or all of it to your favorite, or - best of all in my opinion - give some or all of it to charity.  They're allowing you to allocate your money to Child's Play or the EFF, both extremely worthy causes.

Here, I'll just let them pseudo-rap about it:

I can vouch for Aquaria, Gish, World of Goo and Lugaru as very high quality, really entertaining titles, any one of which would probably be worth whatever number you're going to put in that box (and most of which probably cost more than that number, too, on a normal day).  I can't speak to the merits of Penumbra, but if it's keeping company with the other four it's probably got something going for it.  Bottom line:  This is a great deal, getting you a ton of gaming while supporting the good cause(s) of your choice, so if you're even a little interested you should take advantage of it.  The sale runs all week.