I decided to experiment with divided tanks this week - a decision brought on by not wanting to do the WCs on my ~200 jarred fish. My past attempts to make divided tanks didn't work... the darn things got too dirty, and they were too hard to clean.
In this attempt, I was inspired by the plastic "betta barracks" that you hang off the side of the tank, because these can be easily taken out to clean. To make my own, I used needlepoint sheets to make divided "cages", which I hung off the sides of my tank. I can fit 8 fish in a 10 gallon tank, giving them each a (roughly) 4" x 4" x 5" space. The tank itself is filtered, and I add IAL to the water.
So far the results are good. I had most of the stuff, so the cost was about $20 for the needlepoint sheets. The fish all seem active, and the males are bubbling. The tank also seemed to cycle immediately because I had never cleaned those filters after using them last

http://209.85.62.26/html/emoticons/laugh.gif' border='0' style='vertical-align:middle' alt='laugh.gif' /> Best yet, I've moved 3/4 of my jarred fish into this type of housing, and my water change time has been reduced from 4 hours to 2 hours, which is mostly spent pythoning (aka sitting around and drinking beer!)... sweet!
Here they are: (ugly... I know!)
Whole Tank:

http://i121.photobucket.com/albums/o230/ShirazBetta/BettaCondo1.jpg' border='0' alt='user posted image'>
Birds Eye View 1:

http://i121.photobucket.com/albums/o230/ShirazBetta/BC3.jpg' border='0' alt='user posted image'>
Bird's Eye View 2:

http://i121.photobucket.com/albums/o230/ShirazBetta/BettaCondo2.jpg' border='0' alt='user posted image'>