We don't typically cover road cycling here at Trailspace, but I think these jerseys deserve an exception, especially as I see more roadies out in the spring weather.
Share the Damn Road makes cycling jerseys with a message. The slogan jerseys have messages like "Slow Down" and "Don't Honk at Me" on the back and a mirror-image "Thanks" on the front. They cost $59.95.
If none of the original statements grab you, you can custom order a jersey with your own message for $69.99. (Keep it short and clean, folks.)
Anyone who's ever ridden a bike, run, or walked on a busy road, likely knows where this company is coming from. Share the Damn Road was started by professional cyclist Phil Gaimon to spread the message that cyclists are humans too. He writes on his website:
When you wear a Share The Damn Road Jersey, I'd like you to keep these ideas in mind. Obey the laws, don't be a jerk, don't make it two wrongs, and don't give them a reason to hate us. If someone lets you in, give them a smile and a "Thank you."