Samsung announced a couple weeks ago notebooks and UMPCs with NAND SSDs (solid state discs). The pricing on those is quite high still. This is where Apple could leverage their status as largest Samsung NAND customer to get the pricing down as they did for the iPod nano.

Just imagine a reasonably priced Apple Macbook with no hard-drive just flash memory. Hard-drives are one of the biggest bottlenecks in notebooks. I would be very much tempted to replace my trusty Thinkpad and even go OS X with an affordable MacBook SSD.

AppleInsider reports about an UBS analyst stating that Apple is working on ultra-portable PCs and notebooks equipped with NAND flash memory. The 'fun new products' could be ready in time for MacWorld 2007 in January.
Microsoft is pushing hybrid drives (ReadyDrive) for notebooks by requiring them for Windows Vista certification. Hybrid drives are just half way though, and giving Apple maybe the advantage they need to convert more Windows users with instant (I wish SSD would be instant, but close enough) booting notebooks.