how often do you want to clean, if it is just dust, i recommend something that is electrostatic (basically attracts dust), if you don't mind cleaning once a week, this is a great way to just do dust.
Amazon.com - Washable Air Filter - Made for 20 Box Fan. FILTER ONLY, fan not included. -
i was using this when i moved into our new place, it was dusty as hell, usually i use it for when we travel to friends places w/o air cleaners or worse with pets and dander. since it just attaches to any ol box fan, it's pretty light, if you use it 24/7 you have to wash it once a week. I just run water over it and put it back on the fan turned on (basically letting it air dry at the same time) My mom has it atm, and she likes it, she kinda took it from us the last time we stayed over, been too lazy to re-order one. if you don't have a box fan, theres a combo link there somewhere.
The good thing about it is that it's direct air power/filter. Check this out if you want to just test the waters and don't mind a weekly wash.