Some of the soaps have gay characters like Corrie and Emmerdale currently and Eastenders has in the past.
Brookside had one of the first main soap plots.
Bad Girls had a lesbian storyline.The L Word is a US one.
Sugar Rush.
Willow & Tara in Buffy.
Kima on The Wire.
Joanie Stubbs in Deadwood
Torchwood/Dr Who
Oranges Are Not The Only Fruit
Monica and Norma (a lorry driver for added cliche) from Shameless
Within These Walls
Dr Weaver and partners on ER
Donna & Mickey in Holby
Siobhan Redmond in Between the Lines
Barbara Flynn in A Very Peculiar Practice
Prisoner Cell Block H
Wild West with Dawn French & Catherine Tate
Tamsin and Virginia in At Home With The Braithwaites
Patty Bouvier from The Simpsons
Films...
Tipping the Velvet
Chasing Amy
Brokeback Mountain