I'm from the UK so I'll have to post in £.

You can spend around £150 or something to get a little computer (Raspberry Pi or something) and an ASIC that can mine at 4.5GH/s; if the Bitcoin mining calculator is correct in a month that's around 18.84 Bitcoins.

At current exchange rates that's around £372.16 and the electricity costs wouldn't be that much, this seems too good to be true.

Are ASICs really going to mine this efficiently and if so will the Bitcoin market adjust to the mining changes?