I think I exclaimed "Oh no!" about three times in the first two levels of Vertigo. The good kind of "Oh no!" Taking elements from a lot of other games, and a strong visual similarity with the wonderful 1000 Amps, Vertigo is a free puzzle platformer that's genuinely clever. And hurts my brain. My poor, maligned brain.
Games have certainly explored the possibilities for screen wrapping, where exiting the screen on the left brings you to the right, or dropping from the bottom delivering you at the top. But I've not seen one that allows these limits and borders to be changed as you progress, such that vertical progress becomes a wrapped screen, while horizontal progress opens up, and vice versa. (Although I'm sure I've played a game where you can hold a button to lock a scrolling screen in place and do this.) Then, on top of this, a game where you then find your gravity changed, such that you walk on walls or ceilings as you go (but of course have played many games that do this alone).
The combination of the two could be impossibly distracting, but here - while brain-hurty - it's very elegant. The very first level has this gorgeous moment as you realise the beginning is the exit, after a series of shifts in perspective.
But now, after playing a bit more, I'm seriously having trouble operating a mouse and typing into this window. My brain has rewired itself to cope with the game's changing directions and gravity, and is no longer appropriate for the real world - there's a sort of seasick feeling as menus cascade downward on my we browser, rather than sideways. I'm having most difficulty seeing the way these sentences stack on top of each other. It's taking a bit too long to go away. This is a good thing. And it occurs to me at this late point, oh yeah: it's called Vertigo. I'm experiencing actual vertigo. Coo, I'm slow, and that's clever.
This is a really fantastic little game, and well worth your checking out. And it's free, which is my favourite price. You can pick it up from here in Win, Linux and OSX flavours. And now I have to go stare at a horizon for a bit until I'm recalibrated to planet Earth.