Immigrationboards.com

http://www.ukvisas.gov.uk/en/howtoapply ... a#20768309

Above link says “Do I need to bring any documents with me to the UK? … On arrival, an immigration officer may ask you to show evidence ... This may include... evidence of funding…â€

Carry below set of doc to be on safer side:-

1. Last six month bank statement - which shows that u have sufficient fund in ur account.may be on original bank statement.
2. TB chest ex-ray report - its mandatory they may ask u.

Apart from that they might ask you where r u going to live in UK.
general questions.

chirag