Recently I have been really into finding great (and new) gear for working out this spring as spring is tough because it borders cold, cool and warm, making dressing for an outside jog quite the task.
What's a girl to do? Well, layer of course. Horny Toad has been topping my list for great layering pieces these days. I have especially been getting a lot of mileage out of my Charlie ($46.00) zip-up jacket. It's light enough that it keeps me warm in the beginning of a jog yet it keeps me cool in the end -- So great! The jacket feels almost like your favorite t-shirt because the construction is 'plaited', which means the cotton appears only on the outside where it pulls moisture through the wicking-enhanced polyester from inside against the skin (basically, it breathes really well). I don't recommend this as your only jacket if you're running outside in a colder climate, as it really is a light layer.
Ever since I discovered it, this little jacket has been a staple in my gym bag. You can buy it directly from Horny Toad's site. Oh, and I gotta say, the images do not do the jacket justice.