Get down to Tesco and have a look at some of their deals. They offer some belter deals and the capping option is good.

Most mobile allowances, don't include regualr browsing. That is you get that for free, unlimitted.(check that yours does)

If you are just browsing sites like RLFans it won't count at all towards your limit. Streaming video or audio does though, but if you don't intend to do this then you don't need to worry as you'll get nowhere near 500Mb. As someone suggested if you know you are going to download a lot of data ie. by downloading/updating apps. Then make sure you do it over a WiFi network.

Where have you heard that?

500MB is not too bad but YouTube/Spotify/iTunes Match try and be on Wifi as it will be used up very quickly.

Tesco.....£7.50 per month 500 minutes of calls, 5000 text messages and 500Mb of data AND a free handset. Cracking deal which just doesnt include picture messages (but you can always email the picture) or usage is you are overseas on holiday.