I have two cages right now: A chinchilla cage and a bookshelf, grotto-style cage we made at home. They're rearranged about every time I do an all-out clean at the end of the week, so they're rearranged (and a little better) right now, but you get the point.
Here's the Christmas-miracle, $8 chinchilla cage:

It houses the two girls I'm keeping, Alice and Zap, at this time.

And here's the $6 bookshelf cage we made at home:

Damian and Anthon are staying in the top, and Fletcher is at the bottom all on his very lonesome.

Temperamental rat, he is.

The chinchilla cage for size comparison to a person - in this case, Emily. Measurements are:
30" wide, 18" deep, 21" tall including the base. The shelves both measure 10" wide and 18" deep.

Bookshelf cage comparison. Its measurements are:
About 27" wide, 11" deep (I know, not very deep at all :/) and six feet high. There are five levels including the base with the same measurements as the bookshelf.

Damian and Anthon's three-quarters of the bookshelf cage.

And Fletcher's part. Needs more decorating.
The chinchilla cage contains:
Zap's favorite basket with a pillow
Alice's hanging basket
Rope with wooden beads for chewing
Trampoline hammock
Level blanket
Hanging tube.. thing
Corner hammock
And, now, a litter box
That's all so far. I'm hoping to add to it as I go.

Booskehlf cage contains:
Top:
Damian's favorite basket witha towel and a dog chew rope
Litter box with a "mat"
Hammock
Bird chew toy
Hanging basket, not in picture
Clubhouse
Tube
Bottom:
House, with blanket
Blanket under food bowl
Tube
Box under tube ramp, containing a blanket and strips of towel (Now, at least; peanuts in the picture)
Litter box with mat
So that's my cage situation right now.

I'm really looking into getting a nice new cage.. my eye seems to gravitate towards this one from Super Pet:
http://www.ferret.com/ItemDetail.aspx?ItemNo=650815Not that I don't appreciate my bookshelf cage, but its depth really saddens me because my poor boys don't have a lot of room to run around even if they have enough to move comfortably. :/ Just as well, it really lacks the decoration opportunities I've come to love about all-wire cages.
If I were to get the Super Pet, Anthon would be neutered by then and so him, Damian, Zap and Alice would share it and Fletcher would have the chinchilla cage. But, right now it's just pining more than a reality considering I lack money and room.. but there's always Christmas. :wink: