A good viable alternative to Hotels if there is a few of you is Apartments. Just search google for London Apartments and you"ll get loads, from Student Halls of Residence that aren"t been used for the summer to very nice posh apartments in Park Lane..I found some for £19 pp pn whilst I was looking last week, although some of these were assuming two in a dbl bed.
On another note I am trying to get a train from Manchester , leaving Wednesday, returning on Sunday, but it seems to be a nightmare. 3 Changes on the way back, cheapest tickets 62 quid..Anyone else got anything cheaper from Virgin, You can usually get tickets for 10 quid e/w.
PS ..here"s a link to a cheap halls of residence place..not looked into it to much so don"t know the small print..
http://www.lsevacations.co.uk/ratesavail.htm