You know what the worst part of dealing with ghosts is? It's the ectoplasm. That stuff gets all over everything. If you don't want all your worldly possessions covered in ghost slime, you might just want to ghostbust by proxy in Phantasmaburbia, an RPG adventure by Greg Lobanov, creator of Dubloon, Assassin Blue and a variety of other titles. It mixes in the best elements of classic RPGs, adds in a bit of spookiness and shakes vigorously to produce a tasty ghost cocktail!
Crazy Over Goo is a physics-based projectile platformer that puts you in the gooey guise of a spheroid on a quest to find his pink-bowed friend. Use the mouse to aim your trajectory and try to reach each level's flag in as few jumps as possible. Contend with mid-air leaps, variable environments, gravity, spikes, and many other platform game elements.
Escape from the Underworld is a short exploration platformer that shares some design elements with some of the most successful indie games in recent history: Knytt, Iji, Seiklus, Cave Story, and, well, we could probably go on. In short, Escape from Underworld is a Metroidvania and it's really, really good.