LALU (Leukaemia & Lymphoma Unit at UCH)
Whilst the NHS fund alot, LALU take things to the next level providing things from fridges to medical equipment which helps the whole place run smoother. They fund research placements, nurse education, complimentary therapies (to help you feel less crap - not homeopathy!) as well as helping families through the whole experience. You are in isolation for periods of up to and over a month and little differences go along way.
Anthony Nolan Trust
The Nolan trust take care of a huge part of the admin involved in matching donors with patients. They promote and process new registrations. They run the matching process for the NHS when a donor is need. Often the donor may be in another country such as Germany or the USA and they send a courier overseas and retrieve the donated stem cells within a very short time window so they can be given in time. Ultimately they make the whole process possible and are invaluable. It costs hundreds of thousands to just make the one donation possible. See some FAQS here
African-Caribbean Leukaemia Trust
I am white British and haven't had any direct dealings with Charity but they came to my attention through some work David Haye did promoting them. Whilst it is a very nervy process finding out if you have a donor, the odds are favourable for Western European white people. For ethnic minorities, African, Carribean and any mixed race people the odds are much lower. As our population diversifies and more people marry across old racial divides genetics are mixed into more and more combinations and anyone with an illness from such a race needs a donor but may a real problems finding them. The ACLT do work alongside the ANT to promote Stem Cell donation amongst these communities and to provide education.