Soap - liquid or bar?

A thread about uses for slivers of soap prompted me to ask this question: which do you use: liquid or bar soap - and for shower, bath, or both?

We prefer the liquid soaps because the bottles are neater-looking sitting on the edge of the sink and tub, and there's no messy soap residue to clean up.

But liquid soap and shower gel is significantly more expensive (per use) than bar soap. Does anyone stretch their liquid soap by watering it down, or using one of those foamer pumps? If so, does it seem to work as well?

And would it be cost-effective to make your own liquid soap (not necessarily from slivers, but buying bars, grating them and making your own?)