I'm thinking you could get by with one of the AMD Fusion E450 APUs.
It's about midway between the 'Netbook and mainstream Notebook in terms of performance.
Did you have a budget in mind? HP dm1 11" sub-notebook $350
$375 with E-450 upgrade
AMD E-450 1.65Ghz Fusion APU, 4GB RAM, 320GB HDD, 11.6" 1366x768 LCD w/ Radeon HD 6250M graphics
3.5 pounds and 0.8" thick.