I actually ended up getting an Aqueon Evolve 4 for the girlfriend. Has some softies (mushrooms, anthelia, etc.) and some macros like flame algae. Also has one small chromis. Cleared out the stock media and put in some carbon/filter floss. It's been great, even with the stock light.
So my Aqueon Evolve 8 leaks in the back, had to return it to PetSmart, but the one I exchanged it for also leaks. But at least it leaks a lot less, so I just bought some silicone and patched it up. It's a nice tank for the money, the acrylic is pretty thick too. I believe the other tanks mentioned in this thread are all glass tanks. So if you like glass go with one of them. The one tank that was not mentioned in this thread yet, is the Ecoxotic pico tank, a very nice tank as well.
Recently added a pair of these little guys (Pom Pom Crabs) to the Evolve 4. They look just right in a tank this size. Too big of a tank and they would disappear, since they don't get much bigger than this.
Just giving you more of an incentive by showing the interesting smaller critters you could keep in a desktop tank