I use a hand-held vac but I keep forgetting to charge it (it's cordless) so it's usually back to the old dustpan and brush!
I use the same as JarBax, but mine is the normal model and not the "Pets" version. It's this one:
Shop for Challenge 7.2V Wet and Dry Handheld Cleaner. at Argos.co.uk
It is a Wet & Dry one. Once I had lots of water on the carpet so I used it; it worked quite well.
In the cage it works very well - at full charge it sucks poop and hay very efficiently. It begins to slow down after 10 minutes or so, but unless I'm doing a whole cage clean, that's plenty enough time to whizz round. The plastic front clicks off, then you can remove the filter and filter case which I wash with hot water and soap often, otherwise it stinks of poo when you use it. It comes with a thin nozzle which I use because it sucks the mess up easier, and also a little rubber brush with tiny bobbles on which scrapes the hair off really well. It holds quite a lot - if I didn't have to empty it for cleanliness it'd probably go for a few days until full. It does get poops stuck behind the tube inside the holder bit though. (Sorry, I don't know how to describe the area!!).
Once a week when I change the fleece I use the normal household hoover on the nozzle attachment to suck the hairs and hay off thoroughly. The "Big Hoover" doesn't use bags; it just has a plastic compartment. The fleece is held down with bricks in each corner so the fleece doesn't disappear too.
Perhaps the model I use would work better for you Jarbax?
I hope this helps a bit, STTW. Your project sounds interesting.