I have three go-tos and it depends on what/how I'm drinking.
My first two choices are the standard Glencairn and these "Sipping glasses" from Crate and Barrel. One of those two will really favor most whiskeys and bring out a nice balance of body and top notes. Generally I prefer the glencairn (more comfortable, pretty durable), but I've found recently there are a few whiskies that the C&B glass really does good things for - Angel's Envy last night was one such discovery. The downside to the C&B glasses is that they are FRAGILE, unless they've been updated. Can't tell from the photo.
If I'm having something on ice or as a cocktail, I'll usually opt for one of the glasses I got in a Four Roses gift set last year. Nice, durable, not over-huge. There's a real cutoff point for me and a lot of old fashioned glasses are so wide that I feel like they're designed to allow drinking from your ears as well as your mouth.
On rare occasion (and usually only for scotches) I use a glencairn copita. Despite the occasional fussiness of some of the scotch people, I don't particularly think the copita is particularly complementary to most drinks in a way that justifies the cost.
I picked up a few of the Crate&Barrel sipping glasses the other day. They are a short stemmed, 7oz snifter. I like them
There can't be good living where there is not good drinking....Ben Franklin