While many netbooks on the market today have large 80GB, 120GB, or even 160GB hard drives, many inexpensive mini-laptops use solid state disks with capacities of 20GB or less. While SSDs offer some advantages over hard disks (for example, they’re smaller and sturdier), they’re also more expensive at the moment, which means you’d have to pay a premium to get a 160GB SSD.
Asus has released a Windows utility aimed at Eee PC users who are running out of storage space. Eee PC System Shrinker (download link) will scan your system for unnecessary files that you can delete to free up space. For example, you can gain a few hundred MB by deleting Windows XP SP2 backup files after you upgrade to Windows XP SP3. You can also free some space by disabling system recovery or virtual memory. But you may also take a performance hit or run the risk of mucking up your PC if you disable those features.
Of course there are plenty of other utilities that wil help you keep your disk clean. One of my favorites is WinDirStat, which scans your disk and shows you which files and folders are taking up the most space on your disk.