Here are the ones I've got on best with:
Proraso Green
Speick
Palmolive Stick
Mitchell's Wool Fat
Beyond that, I've had mixed results with:
DR Harris Marlborough - takes a lot of effort (check out antdad's hard soap tutorial to see what's involved)
Musgo Real - creates a stiff lather that dissipates quickly
Trumper violet - nice smell, shame about the lather
Valobra - not bad, but not up with the top list
Neale's Yard - very slick but no cushion at all
And I've been disappointed with:
Nanny's Arabian Nights - much harder to lather than I expected it to be (but I would point out that I was impressed with a sample of Down Home Summer, so I may have had a dodgy batch - I bought it on BST so I guess the previous owner had been similarly unable to get a consistent lather)
Stirling Scot's Pine - not easy to lather and the pine oil irritates my face (another BST acquisition, so I guess the previous owner was equally unimpressed)