Oh, you discovered one of Stu's favorite webcomics. The math geek in him just adores that comic. ^_~

(On that topic, have you ever read Thorn? http://www.mimisgrotto.com/thorn/ It's a great little webcomic. It's about Rosie, a typical 5 year old girl in the 1950's whose dream is to take over the world. XD)

I heard about masking fluid back in high school, but I have to admit I barely use it. I really should try playing around with water colours more.