You are only paying for one IP address. Not sure how homechoice operate but you either install a router which allows the one address to be shared by many other devices like XBox and PC at same time. Uses a thing callled "Network address translation".
If for whatever reason you don't want to buy a router or you can't connect one then Homechoice will probably charge a few quid extra and give you a a few addreses.
I'd certainly go down the router route cos its provides security in the process of doing network translation. If your connected direct to the Internet as I suspect then you PC or Xbox are wide open to nasty hacker people and lets be honnest the operating systems arn't so secure.
The usual suspects make routers and one might think you may even want wireless but then you said your using Homplug which is a wireless alternative.
You might like to think of the router as a 'splitter'. Connect one port to the homechoice box and the other 4 can go to PC's, Xboxes, laptops and so on. If you get wireless then you can even surf the net on the bog or in the garden assuming you have the little receciver (new laptops have em built in).
http://www.amazon.co.uk/exec/obidos/...127135-7055975
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