DeepBlue Professional (I think it is the 8B). It is an 8" rimless cube. They make a 12" cube as well.
They also make a small filter that fits the tank well. 4W
27 Watt desk lamp. Uses a FML27 bulb, 6,700K. Four short tubes side by side. It has better light spread than a CFL.
8 hour light cycle comes out to $13.67 per year to run the tank (at $.12/kW), or $16 for a 10 hour light cycle. Sounds cheap to me.
They can be hard to find, but they have a good price point (unless the store marks them way up. I know of a store that marks up the DeepBlue 5 Betta tank to almost $50, I normally see it for $23). The glass is low iron, really clear. Thin black silicone seams. I think the tank and filter were less than $45 after taxes.