The guys from Sweetwater demo a bunch of pedals that will help you create synthesizer sounds without having to learn to play keyboards. As comprehensive as this is, it just scratches the surface. Look for more pedals that create synth-like sounds soon a Guitar Moderne.
Earthquaker Devices is one of most successful pedal manufacturers to emerge from the boutique effect world. By offering solidly constructed, great looking and sounding pedals at an affordable price point, they have shaken up the market like a 5.0 trembler. Though they offer standard effects like overdrive, fuzz, distortion, and compression, Earthquaker also occasionally pushes the pedal envelope with something like the Arpanoid ($225 list).