Silverdream - according to my database, about 76 of them!! Admittedly, a couple of them are due to recipe or ABV changes, but I've certainly tried a fair few. Durham are well known for producing very light, hoppy, quenching session bitters, but as Steve Gibbs, the owner and brewer is keen on tinkering (!), he has produced beers ranging from the 3.7 abv Durham Gold, through beers like Black Velvet (4.0), up to White Magic (6.0 and 7.0), Benedictus (8.5), and the very dangerous Imperial Russian Stout (10.0!!). On the whole, Durham produce some very good beers.