Does anyone have advice on cleaning Lego?
A few years ago I bought a box of assorted Legos from a pre-teen selling his collection. I haven't looked at it in a while, for various reasons (no space for Lego, little money, grad school and no time...). I was inspired to continue sorting the stuff today, and noticed that a number of pieces are not at all clean.
What is the best way to take care of this? I'm talking about gunk in crevices (the recessed front areas of a rowboat, the corners of the stairs of an old-style spiral staircase). Reaching some of these areas is difficult. I'm not sure what this kid did to his toys, but yuck!

Also, what is the best way to deal with scratches in the printing? I've got some old castle walls with stone patterns around the windows, and one has a spot right in the middle of a "stone" where the darker gray has been worn off and the lighter base color shows through.
Thanks for the help.