CNN.com - Flat-screen prices finally tumbling - Aug 16, 2005: "Some major retail chains continue to charge a premium for plasma and liquid crystal sets, pocketing 25 percent profits on larger models, Patel said."
I have had friends argue with me saying that Retailers make nothing in margins. Here is a quote saying some make as much as 25% on flat panels which is one of the most competitive spaces in consumer electronics at the moment. And also this is an american article. In Australia Retailers enjoy much larger margins (apparently due to smaller volumes sold - but i think its due to a lack of competition in the Australian retail market!)
If you are looking to open a business in Australia, consider consumer electronics retail, low margin high volume model.
If executed correctly, you won't go wrong.