i did have a large wire cage for my first three hamsters as can be seen here with my current hamster, Doris, in it: http://img.photobucket.com/albums/v502/XDOW/cage.jpg
dimensions on it are roughly 24"x12"x24" high. (maybe slightly higher)

which is brilliant for them, adding tubes and extra levels for them to explore - and they get to climb on the bars.
it's a bit bare in the picture as this was only a few days after i brought her home.

however with Doris, she started to chew the bars on it constantly, and after trying everything i could think of to stop her
- new toys, covering the cage in paper, giving her as much time out of the cage as i possibly could
and this not improving the situation, in the end, due to lack of sleep and for want of an easy life, i relented and she now lives in my old glass aquarium.
to be fair this isn't a good size for her - it's 24"x12" of floor space. i was going to upgrade her to a 48"x12" aquarium, which is just sitting in my ex's garden, But this was previous to him being my ex and... things have gotten messy since then (all down to him as well, immature git)
and as a result, i'm never going to see the tank again.
utterly gutted though, it would have been a brilliant size for her.

she seems to have a fetish for chewing metal though - as i'm typing now, she's behind me chewing on her water bottle holder.