With temperatures warming up, you're more likely to go outside for a run or bike ride. But daylight is still at a premium, meaning that if you want to exercise before or after work, you still have to deal with the darkness. The Nathan LightSpur RX is a relatively inexpensive way to help ensure that you're seen while exercising in the darkness. The very bright LED lights, which resemble high-tech spurs, attach easily to your shoes. You can change the color to red, green or blue, and choose either a constant light or a strobe setting.