Google's newly announced Chromebook comes with 2GB RAM and a 16GB SSD drive, the first netbook, the Asus Eee PC 701 came with 512MB RAM and a 8GB SSD Drive. With the price of RAM at an all time low (you can pick up 24GB RAM for under £100), it might make sense to build a computer that relies on RAM exclusively both for long term storage and system memory.
The advantages of moving to RAM only are multiple; much faster read/write speeds compared to SSD and hard disk drives, simpler layout (basically just multiple memory module slot), no fragmentation, very little heat dissipation, and much easier upgrade path.
The only hardware issues would be long term data retention, although that can be solved by re-engineering the battery circuitry that's on every computer motherboard as well as the ability to dynamically alter the amount of memory dedicated to the system.
Then there's the other not so small issue of getting the operating system to boot from the memory somehow from an image stored on the computer (on a flashable ROM) which can be upgraded remotely, not unlike Chrome OS.
Given that we're at an inflexion point in the world of technology where former paradigms are gradually being dismantled (fat OS/thin client, Wintel, x86, mobile vs desktop), it does make sense to look at the base computing unit from another perspective.
Now consider this, by this time next year, quad core ARM-based tablets, smartphones and ultra thin netbooks will be the norm, Windows 8 for ARM will almost certainly have been launched paving the way for some exciting possibilities like month long standby, day long battery life and exotic form factors.