Many Android owners seem to have a love/hate relationship with live wallpapers - no matter how stunning they are, they generally zap performance and battery life too much to be used for long. Here's one that might work on both sides of the coin: meet Solar Wind LWP.
As you can see, it's... well, it's a bit hard to describe. It mainly consists of multi-colored strings of dots swirling around. A video can do it better justice:
Video courtesy of YouTuber bmmahfood.
The app seems to be wildly popular: it's been on the Market for 19 days, and broke 250,000 downloads after just 12. Ratings are generally very positive, and the app has an average of 4.23/5 stars - very impressive. It apparently runs quite well on most devices, and doesn't suck up battery life (or, as much as usual). To be fair, though: I saw a Market comment about it not running well on an EVO, and sure enough, when I tried it on mine I found it resulted in lag. Again though, most other reviewers said they had no such issues.
The author's description:
This is the most stunning live wallpaper you have ever seen, I promise. Key features：
1.The most stunning effect within a package which size < 64K
2.Well implemented with OpenGL and highly optimized
3.Five default effects are bundled
4.Fully customized setting options
It's free and absolutely tiny (<64K!?) - what are you waiting for? Give it a shot, and if you have any issues, post below with your device.