Ultrabundle for Linux

The Puppygames created a bundle which includes:

• Ultron
  Unique retro-futuristic sound and graphics, player responsive difficulty, and a subtle system of tactics combined with classic gameplay make Ultratron a fun and hypnotic arcade blast.
• Titan Attacks
  Titan Attacks has the same easy-to-learn and addictive gameplay of the classic arcade shoot 'em up, but is packed full of extras - new features, new strategies, and stylish neo-retro visuals.
• Droid Assult
  Discover a unique tactical arcade shooter, with the fun addictive gameplay of classics like Paradroid and Quazatron
   

The usual price for this three linux games is $59.85, but now you can get them for only $4.97 at their website.