If you are a student DJ, in a band or have a concept for a future business it is a good idea to purchase the domain name that you would like to use. This will stop anyone else from registering it. If it has already been registered by someone else it will give you time to revaluate which URL you are going to use and purchase it. If you have the time and resource to do so it is also worth setting up a basic website. There are a range of reasons why this may benefit your venture in the long run. Two of the main reasons are:
1: Google adds more credibility to older URLs that have content assigned to it. This may help your websites SEO efforts (getting to the top of Google for certain words such as your name etc) in the long run.
2: By having a live web presence your pages may start to attain inbound links from other websites. Inbound links is a key factor in how search engines (such as Google) assess the credibility (importance) of a website.
I do not use 123reg.co.uk for my website hosting (I currently use LCN). However the deal that they are currently offering is the cheapest student deal that I have seen. More information can be found here: http://www.123-reg.co.uk/studenthosting/