I send my 35mm negs to Superstore (Walmart / Target equivalent). Interestingly the colors seem pretty accurate when compared to prints from a proper lab. The resolution is just enough for web use. For 5.99$ / 120 exposures / 1 day service I can't complain at all.
I have also used the Nikon 4000 ED for slides and negatives and boy, that thing is slow.... For slides it's fine since you can just leave it on its own, but for negs the wait and the impracticality makes it a monk's job... I use the 4000 for slides exclusively now. One day I'd like the Coolscan 9000, but that's far in the future, probably after a full frame Digital
I haven't tried flatbed but it looks and sounds like it's more cumbersome than the Coolscan 4000. I'm not interested unless I get one that can scan MF.
@tuco: what kind of scanner do you use for your LF and MF?