Devin and I swear by aspen.  

Carefresh Ultra is awesome if you can afford it.

Regular Carefresh is kinda dusty and has a weird smell, but it's absorbent, very soft, and fairly cheap. Yesterday's News and other recycled paper litters are supposed to be pretty good, although I've never tried them.

Aspen is supposed to be safe, although I don't care for its smell either.

Walnut is very cheap, absorbent, handles smell pretty well, but not the most comfortable for walking on, so it makes a better litter than a bedding.

Newspaper, cloth, and corncob all get smelly very quickly, so they have to be changed often.


I use walnut for my rats' litter, cloth and shredded newspaper for bedding, and Carefresh for my snake since the dust doesn't seem to bother him.

We've been using Swheat Scoop for our rats and scooping it once a day, and I LOVE it.  It's typically a cat litter, but it's made from wheat so it's safe for rats too.  If you scoop it daily, you can go up to a week and a half without changing it out completely, so it's economical and nice to our wallets.  

Does it smell weird? I used a wheat-based litter this last cage-cleaning and it smelled awful, like fermented fruit.

Jessi

I used to use wood shavings but the place I got them from wasn't a company and just shoved any kind of wood into them and they were a little dusty. Now I put newspaper or cloth onto their wooden floors. In the place they use as a toilet area they have the corner of cereal box which is thick(ish) cardboard.
I'm in the UK so I don't think I can get Aspen or Carefresh without shipping whihc my parents would no way pay for.

We use Yesterday's News religiously now. I've used newspaper, Carefresh, Carefresh Ultra etc and YN is my favorite. CareFresh ultra is good, but it's expensive for my 6 cage crew. I've been able to leave the Yesterday's News in the cage for up to 2 weeks with no problem.   But I change it out at 7 days to prevent odors problems..

-Melina

No, it seems the unscented YN for cats is the exact same thing.

Jessi

I use aspen shavings for rats and snake. Works very well for us!

I've used a lot

Carefresh: REEKS worse then the rats

Aspen: nice if you like the smell

Wheat cat litter: great except that the rats ate this instead of their food, by the end of the week they'd have no litter left because they ate it all.

Walnut shell: by far the best, scoop it like a cat box every day and it's great!

more but I don't remember.

Zechnas

I use Crushed Walnut shell and I love it! it's not dusty (although I have heard that the Kaytee brand is), is not scented and if scooped every day lasts my 14 rats about a week and then I do an entire cage cleaning. The rats don't mind it on their feet and they are only walking on it if they go to the very bottom of the cage.
The only problem some people might have with it is that it can be heavy if you buy it in 50lb bags and it costs about $25-30

I have used Both scented and Unscented Yesterdays News and with YN I had to dump and scrub the trays every 3 days, I bought a bag of Sweet Scoop when it first came out and it seemed very dusty so I never used it, CareFresh was too dusty and smelled bad, CareFresh Ultra smelled weird (but not as bad as original) and when I use it in the travel cages for rat shows (because it looks perty) it really doesn't control the stress poo smell very well.


I have never used Aspen for rats but I have for a Hamster and I don't remember if I liked it or not.

Zoiks! Where do you get your walnut?! I only pay $10 for a 50lb bag at my local pet supply store.

My gf and I use CellSorb (when we can find it) or Yesterday's News, when we can't. They are both excellent at odor control. We also use Carefresh as a backup (and for the guinea pigs).

I think what's best is up to you, as long as it's not pine or cedar--certainly factors like price come into the formula!