If you can live without a CD drive, take a good look at the Asus EEE 1000H, or the Dell mini 9 or mini 12.
If you will find a CD drive useful (for putting your music CDs on there)*, then get a regular laptop.
If you browser ebuyer.com and amazon.co.uk, you will be able to find laptops for �299 or there abouts, from the likes of Acer, which will do everything you want and more.
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* Yes I know you said you don't listen to music with it, but you never know what you may want to do with it in a year's time.