How Long Until Large Flash Drives Become Affordable?

Flash drives are a nifty thing, going up to 2 gigs for only $10 - $20 depending on where you buy. We can all realize the potential large flash drives would have over spin drives - much fast and less wearing out. But at roughly $10 per gig, 500 gig drives would be outrageosly priced. Is any company working on making this technology mainstream? And if so, how long until solid state drives are as affordable as today's spin drives?

I was excited about this for a while, but I don't think the performance is there. If I could get a 20gb boot/os drive for $100-200, I might consider it. The negligible seek times are impressive, but the data transfer times are not yet up to what a normal hard drive can deliver, let alone a raptor. I think the read/write longevity needs to get much better also. At the rate things are going, though, I expect to see some viable ones in a year or two.