Dustforce
Dustforce is a broom based platformer with lots of acrobatic action. Clean the levels and use your broom for close combat.
Download (10$)
There is no demo available but you can check out the old prototype from 2010
Midnight Mansion HD
Midnight Mansion HD is a huge retro styled platformer with 11 different themed mansions to explore. Each mansion offers dozens of nicely designed rooms with treasures and keys for you to collect (and enemies and traps to avoid). The detailed map is also pretty nice because it shows you all rooms at once (including keys, doors and enemies).
The game is available for Windows/Mac and the game is pretty big as already mentioned (The demo alone takes already around an hour to finish).
Download (17$ / Demo available)
Note that the installation of the game takes around 5 minutes. (Many small files to copy)
Treasure Adventure Game
Treasure Adventure Game is a charming exploration platformer that features a big non-linear world with 18 islands to explore. It was over 2 years in development and the developer describes it as Super Mario Bros. 2 meets Wind Waker.
Download (104 MB)
Home Sheep Home 2
Home Sheep Home 2 is a charming single screen puzzle platformer where you have to guide three different sheep (small, medium, big) through various landscapes. Collect socks and make use of your environment to solve the puzzles.
If you want to see how the game looks in action consider to check out this video walkthrough that shows the entire “Lost in London” episode (which can be played for free online).
Play Online (1 Episode)
Download (10$ / HD Version with 3 Episodes + Bonus Content)
Photonstorm was involved in the development of Home Sheep Home 2 and has also written a comprehensive article about the creation of the game. He has also created Cat Astro Phi (a charming top down action adventure with Game Boy graphics)
Trine 2
Trine 2 is an amazing physics based 2.5D platformer where you control three different characters: a wizard (magical powers to move objects), a knight (sword & shield) and a thief (grappling hook & bow and arrow). Beside local co-op the game also features online co-op for up to three players.
Download (15$)