Personally the little Clios are cracking fun. I love my Cup to bits and you can pick up either a Cup or a 172 as edde says for seriously good money. My Cup is probably worth £8k max which would leave you like £6k left. You could invest this towards a house or savings.
Theres alot of cars out there though so shop around. The CTR is really nice and well built of course and possibly easier to live with on a motorway run as the Clio seems to be a bit leggy and noisy.
As everyone has said go and check out a few cars though. Id definately want to test:
172/Cup, 182, CTR, Leon Cupra R, Integra Type R (new one and old one). Oh my there is so much you can buy for £14,000 ..... Look man all Ill say is dont buy the first thing that comes along, and look at magazines and books like Parkers.
A car may be cheap but think about running costs, servicing, fuel economy etc.