Yup, often. I thought I was meticulous, but I wouldn't eat off the inside of my fenders.
You can remove some dirt and dust with a bucket of soapy water and a rag. Keep it away from the electricals though. Once you get the major goop off:
Carb cleaner is good for getting stuff off metal parts, and degreaser (I have some sort of orange stuff) is good for the rest. Don't let it sit for forever on the paint, though. If the goop is really heavy, scrape it off gently first, then break out the chemicals.
A long skinny screwdriver is good for scraping heavy goop off (just be careful not to scratch anything except the goop) in tight places.
Terry cloth towels are good for soaking stuff up and cleaning easy-to-reach areas. Cut up t-shirts are good for getting in smaller nooks and crannies. If it's an extra-small nook or cranny, use your screwdriver to push the rag into it and wipe away all the glop.
Q-tips are just good in general, as are old toothbrushes.
0000 (extra extra fine) steel wool is good for cleaning chrome.
When you take something apart, clean it thoroughly before putting it back together. Spraying down nuts and bolts with carb cleaner or letting them soak in CLR for a few minutes will help clean them up, but make sure to dry them off well (if you use CLR) or else they'll rust back up again.