I thought this would be of some interest. Here are the links:

C|Net: Game console prices, from 1976 on
http://news.com.com/2061-10797_3-6074677.html

Curmudgeon Gamer: History of Console Prices (or: $500 ain't the worst...)
http://curmudgeongamer.com/2006/05/history-of-console-prices-or-500-aint.html
(Click on each image here for a larger view of each graph.)

Integra.