http://www.indieroyale.com/collection

Log in using your Desura credentials, or just open one of your IR bundle purchase emails.

According to the post on steam, these are the bonuses:
5 Bundles = Chiptopia: This album contains the awesome best-of from 8-Bit Weapon and ComputeHer.
10 Bundles = Super Space Rubbish (+ OST): An addictive arcade title for Windows, Mac, Linux and Desura where you can defend yourself from waves of enemy attackers, energy leeching space vampires, huge warships, and natural phenomenon. Plus an OST with tunes from Datassette.
15 Bundles = Fireball: RadianGames’ acclaimed action game for Windows, Mac and Desura - dodge swarms of enemies and lead them to their destruction in this movement-oriented arcade game.
20 Bundles & Beyond = Stay tuned for more unlocked bonuses!

I have 12 so far. Space Rubbish looks pretty good, judging from the video.

I gave Space Rubbish a little go earlier today and it's pretty fun.

(I have all 16 bundles released so far >.>)

... Sixteen? I only saw fifteen. And I -know- I didn't miss one because the site would say so if I had.

Thy Rewardz counts as one: http://www.indieroyale.com/members/eyeball226

But it wasn't released. It was a gift. :p

Eh, okay, fine.

This is actually a pretty brilliant idea, and it's something I think the HIB would benefit from as well, even if it were just a way to manage your existing bundle downloads.