In reply to educatedfilm's question, you can use chromatics in progressions, just use your ear to judge how something sounds. Check out this progression I wrote the other day. It has a chromatic descending bass line and a wide-spread arpeggio pattern.

Am, E/G#, G, D/F#, F, E

I'll tab it out, but please don't steal, ok? Feel free to comment on what you think about this song. By the way, this song is kind of hard to play, physically (moderate tempo)

Am E/G# G
|------------|------12----|------------|
|------13-15-|---------12-|------12-13-|
|------------|------------|------------|
|---14-------|---14-------|---12-------|
|12----------|11----------|10----------|
|------------|------------|------------|

D/F# F E
|------10----|------------|------797---|
|---------10-|------10-12-|----------9-|
|------------|------------|------------|
|---12-------|---10-------|---9--------|
|9-----------|8-----------|7-----------|
|------------|------------|------------|

Copyright 2002, Jared Wilson

P.S. - The tab won't line up right, so copy + paste into NotePad