Recent rumors shows that a new 50mm f/1.4 IS lens is coming in 2013. The old EF 50mm f/1.4 was release in 1993, and recently got a price drop to $299. It sounds like a 1.4 IS variant is going to be announced in 2013. There also rumors an f/1.8 IS version existing. Don’t expect such a lens to be much less than the $800 that the EF 24 f/2.8 IS, EF 28 f/2.8 IS and EF 35 f/2 IS all approximately cost.
The EF 85 f/1.8 is also in the works with an IS version.