Good source for genuine batteries I'm looking to source a genuine original size battery for my HTC Desire. I'd rather not fork out the RRP of ~£35 but lots of the cheaper ones have bad reviews. Will anything much less than the RRP be fake? Does anybody know of any reputable sources in the UK?
I always buy batteries on eBay.  "But that's not reputable at all," you might say.  Indeed.  However, I find that as long as you search for the specific part number (e.g. BB99100 for the Nexus One / Desire battery) and ensure the posting contains pictures and guarantees it's genuine, then you'll be OK.  EBay sellers avoid lying about that sort of thing because their reputation will quickly be damaged.  Also ensure the seller has a good feedback rating (97%+).

Here's the cheapest new battery from a very reliable-looking seller that I could find.