[T]o experiment with substituting borosilicate glass for ordinary glass in a sexual device was not a venture into the unknown.
Ritchie v. Vast Resources, Inc., No. 08-1528, slip op. at 5 (Fed. Cir. Apr. 24, 2009) (Posner, J., sitting by designation) (holding patent for "sex aid . . . fabricated of a generally lubricious glass-based material containing an appreciable amount of an oxide of boron" invalid for obviousness under KSR Int'l Co. v. Teleflex, Inc., 550 U.S. 398 (2007)).
