At least here in germany (i don't know if anywhere else) Amazon App-Shop is offering usually paid apps (all in all amount of 100 Euro) for free!
This offer is only valid on 27 & 28 June, so be quick or be dead, lol.
There are cool apps inside, like Root Explorer, My Backup Pro, Sonic...
Take a look yourself:
Please let us know, if this offer worked for you in other countries!