The LM4250 (aka NJM4250) is a interesting op amp. They're nice for making micropower buffers. Or novel VCFs. But I'd never found them that great for typical op amp based distortion circuits.
Recently, I've been playing with them and came up with a odd distortion circuits using one of these chips. The circuit is unusual in that uses no negative feedback (except for a small value "gimmick" cap to head off , resembling a comparator-like fuzz. However, it doesn't behave or sound like one.
Anyhow, it seems this chip could be good for "out-of-the-box" circuit ideas. And Mouser sells 'em cheap. :)
The 4250 is used in the Ranger ParaExciter, a low-Q bandpass booster ... works good with a JCM800 ...
(http://www.lynx.net/~jc/rangerSmall.gif)