This is a system I don't know at all, and at a cursory glance I don't think it interests me especially, but it looks to a reasonably good deal if you like what they're offering:

"All the roleplaying games in this offer build on the rules introduced in Vincent Baker's fantastically original 2010 RPG "Apocalypse World." This collection omits Dungeon World and its spinoffs, which were featured separately this past December.
This offer runs until Wednesday, September 16.

http://bundleofholding.com/presents/Apocalypse

STARTER COLLECTION (US5.95 - retail value $27)

• Monsterhearts (Buried Without Ceremony, retail $10)
• Monsterhearts: Blood of Misty Harbour (Buried Without Ceremony, $5)
• Bootleggers: Smuggling Run (One Seven Designs, $7)
• Cartel: The Ashcan Edition (Magpie Games, $5)

BONUS TITLES (threshold starts at $14.95 - retail value $44.50)

• World Wide Wrestling (NDP Designs, $10)
• Monster of the Week (Evil Hat, $12)
• Legacy: Life Among the Ruins (UFO Press, $12.50)
• Deniable (StoryWeaver Productions, $10)

As usual the way that this works is that the sooner you buy this, the cheaper the bonus collection. They're DRM-free PDFs. There will also be at least one extra bonus item added as the offer progresses, anyone who pays the bonus rate will get it/them.

Ten percent of each purchase (after gateway fees) goes to the Electronic Frontier Foundation.

Usual caveat - The main reason I know about this offer is because I'm on the list to get this stuff free if I want it. In this case I don't particularly, but it seems like a reasonable offer. If I think these are bad deals I'll say so.