I have a CentOS VPS from UKWSD and I'm getting inbound traffic that I cannot understand.

The VPS was setup yesterday and I installed vnstat this morning around 10am, since then the server was basically idle and doing nothing from 12pm but it's showing activity inbound which is way over what it should be and i'd say the outbound is pretty much over to top too.

Here is vnstat (snapshot taken at 10:30pm GMT) http://i.imgur.com/XnORb.jpg

Here is the iptables http://pastebin.com/uGxX2Ucw

The reason I'm concerned is..
1) I have no idea why this is happening, and I like to know what's going on :D
2) I've calculated (briefly) that this pointless traffic would use around 15-20GB of bandwidth per month, and when your on a 150GB limit - it's quite an issue.

I'm struggling to understand this and I thought I'd get some advice before asking my ISP (and risk looking completely stupid)

Regards Matt