I have mostly-waterproof, unlined, ski gloves designed for spring (wet/slushy) skiing. None of my biking gloves have fared well in rain.

http://www.skiwarehouse.com/skiwareh...ve-P18693.aspx
(fortunately, they didn't used to make them this ugly.)

In other situations, I am a huge fan of thin wool or polypro liners. They will not keep you dry, but will help retain heat when wet.