A gameplay/trailer video here:A simple, accessible-yet-difficult, fwooshy, “feel good” flight sim. Blow things up on an infinite number of procedurally-generated islands, but watch out for volleys of missiles; when you die, you're dead.
https://www.youtube.com/watch?feature=p ... GUz_L-s-vM
Get it here: http://nihilocrat.itch.io/sky-rogue
Official subreddit here: http://www.reddit.com/r/skyrogue/
You can pay what you want for it.
Also, it's in an Alpha state, so there will likely be plenty of changes before official release. Planned features include things like multiplayer (most likely co-op) and more variety in planes, terrain, enemies, etc.
Best of all: it runs real nicely on low-spec machines like my laptop.