Tim's own site here lists the different types of filters and how they work.
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.