There's only just under 30 hours left to donate to the pay-anything, charity-driven Humble Indie Bundle, if you haven't already, and to say thanks for the nearly $700,000 raised so far, they've just made the deal even sweeter.

First, Machinarium developer Amanita Design has added their second point and click adventure Samorost 2 — still also compatible with Windows, Mac and Linux — into the package that already nets you 2D Boy's World of Goo, Frictional's horror-adventure Penumbra Overture, bit-Blot's Aquaria, Wolfire's rabbity-combat game Lugaru HD, and Cryptic Sea's physics-based platformer Gish.

Second, a cryptic email by the bundle's organizers has promised an (apparently accidental) surprise to anyone that pauses the above video around the 1:17 mark, which I'll save you the trouble of doing and note that the copy states that if the bundle reaches the $1 million mark before it ends, the developers have promised to release the full source code for Gish, Penumbra and Lugaru.

With just $300,000 left to go before they hit that mark, it's looking not entirely outside the realm of possibility. Go!

The Humble Indie Bundle [Wolfire]