Tim's own site here lists the different types of filters and how they work.
http://www.tropicalfishandaquariums....re/Filters.asp
Filters shouldn't need to have too many parts or need to be cleaned too often...the bacteria does most of the work.
I have AquaOne Clear View HOB filters on all my tank (only HOB brand available in my LFS' ) the only parts they have are the water inlet tube, water flow knob, impellor and the 2 filter media cartridges...all of which are very easy to remove and rinse/clean if needed. I have never had any problems with them at all and I very rarely need to clean the actual filter itself.
Of course these filters aren't an option if your tank has a completely enclosed lid on it.