Like ck777, I can't believe I've missed a gin thread too.

Tanqueray Ten gin is my preferred martini gin. Dry, with two lightly brined manzanilla olives (unpitted). Stunning, and quickly draws the martini veil over the world.

I tried Monkey47 neat recently and loved it as a digestive gin.

Regular Tanqueray gin works well in a G&T. Fever Tree Tonic (the blue label "lightly sweetened" variety) is my preferred tonic water, but that variety can be hard to come by.

Hendricks gin is also very good.