The strangest stand at the London Music Show was Amazing Nails 4 Guitarists, a tiny company run by "international celebrity manicurist" Midge Killen. She does Paul Simon's nails when he's in London, is a technical advisor for the London International Guitar Festival and holds a regular nail clinic in California for her US clients...
More than you ever wanted to know about guitarists fingernails:
1. The four basic methods
2. Many pages of The Guitarist's guide to fingernails
3. A 1969 patent for Method and apparatus for filing fingernails of guitarists, banjo players and the like
4. The history of guitarist fingernails 1554 - present
5. Creepy guitarist manicure masterclass on YouTube.