Many cyclists we know whine about the rain. It's wet! Whatever. Get used to it. If you ride, you're going to have to ride in the rain someday. Some days, you're starting in the wet and riding into dry or starting in the dry and riding into rain. Rain happens. Sometimes all day for days on end. Get yourself a good rain jacket; you'll bemoan the price until you use it, then you'll be happy you bought it every time rain is forecast. Giordana's Hydroshield Taped Rain Jacket is one you'll want, as it is not only breathable, but it packs small.
Breathability is owed to the material. It's called Sentry. Like many other jackets, it's a laminate. Unlike other laminates, it possesses no pores. Rather than having micro pores that can potentially stretch and crack from use or get plugged up by salts and oil and dirt, the seemingly "solid" membrane actually uses its molecular structure to suck in vapor and pull it through the other side and out. And, as the name implies, the seams are taped to make sure water doesn't leak through.
Also thanks to the material, it is thin and light. It packs into the chest pocket just by turning the jacket inside out and stuffing. This pocket is designed to be big enough for an mp3 player and even has an interior port so you can run wires through the mesh side of the pocket up to your ears.
The fit of the jacket is close to minimize wind drag and the rustling that can occur when jackets flap in the wind. There is some stretch to Sentry, but it's more on the bias than directly horizontal or vertical. The front zipper is waterproof and is protected from your clothes by an interior draft flap.
The jacket is finished for both comfort and safety. There is elastic at the wrists and waist to gather the jacket and keep water from running up inside. The hip regions on the jacket have stretch panels in Ametista fabric to keep the fit close. There are reflective strips on the back of the hips and behind the neck for visibility. There is also an accessory hood available separately. This fits around the neck and close to the head and is designed to be worn under your helmet.
The Giordana Hydroshield Taped Rain Jacket comes in Black. There are rubber Giordana logos front and rear. Sizes run from Small to XXX-Large.