In order and of the last decade.
3.
London Midland / London Midland:City (designed by Best Impressions)
2.
First Great Western's Dynamic Lines / Local Lines (designed by the former Lambie-Nairn)
1. Secro's
Caledonian Sleeper (designed by Weber-Shandwick Design)
It's a shame to see the London Midland livery gradually disappear for the over complicated, confusing and overtly fussy schemes on the WCML, while Dynamic lines even to this day looks good, and it's a shame First has turned against it for the dismal and over complicated green livery for the great western. But the simplicity of Caledonian Sleeper really does it for me, beautiful shade of Teal, simple and very clever logo. Best since BR in my opinion!
You can read about each of the liveries on the designers websites here:
London Midland / Best Impressions:
http://www.best-impressions.co.uk
First Great Western / Lambie-Nairn
http://www.lambie-nairn.staging.athlonproduction.com/case-study/first-great-western/
Caledonian Sleeper / Weber Shandwick Design
http://webershandwickdesign.com/portfolio/caledonian-sleeper-branding/