http://gavinandresen.ninja/utxo-uhohToday, the UTXO database is about 650MiB on disk, 4GB when decompressed into memory. DRAM costs about $10 per GB, so you need to spend about $40 on memory if you want absolute fastest access to the UTXO. Not a big deal....
'Assuming the UTXO set continues to double and RAM prices continue to drop 20% per year, next year youll have to spend about $64. Ten years from now, over $4,000
'....
Looks like there's a fork planned to solve this BTC problem at 2016.
What is the solution they are using?
The only radical solution I know of is with the lightning network proposal.