The PS3 is the poster child for this type of tactic, at their beginning they sold for $300 less than their cost of goods.[1] Their failure has nothing to do with locking in a market due to price. [1]http://www.gamasutra.com/php-bin/news_index.php?story=11740
It wasn't enough. They may have been selling at a loss, but the introductory PS3 prices were at least twice as much as the Wii. When Sony began to cut prices, sales jumped. A $100 price cut in 2009 doubled sales: http://kotaku.com/5356885/npd-ps3-sales-gain-ground-on-price...
As far as I remember, Nintendo always did that, selling each console at profit, however small that may be, starting from NES, to Super NES, N64, Gamecube and now Wii (and I guess, soon WiiU).
So Nintendo was the only manufacturer who did not apply the "razorblade" model of the other console makers, which is understandable since they were and are a videogame company only and thus never had any other branches which could have been able to subsidize their console business in the beginning (unlike for example Microsoft).
I think the first console Nintendo made that actually sold at a loss is the current 3DS handheld and that may be after the very fast initial price cut after the slow reception on the market.
Sony's problem there was that the PS had very expensive parts, so they had a harder choice to make on pricing to be competitive.
Nintendo, meanwhile, couldn't keep Wii in stock for more than half a day until something like 2 years after launch, so they could have raised the price about $100 and not lost a sale