Free Actions

http://browse.deviantart.com/resources/applications/psactions/?order=9&alltime=yes

Large collection of high quality actions from Deviant Art.

http://graphicssoft.about.com/od/photoshopactions/

An article from about.com with a detailed, annotated list of photoshop actions.

http://www.liknes.no/photoshop

Border, text, 3D, filmstrip and puzzle actions.

http://www.thelightsrightstudio.com/photoshop-tools.htm

Black and White conversion and toning, compensation filter action, color enhance, temperature, color overlay, diffuse glows, cross-processing, Digital Noise Reduction, Digital Velvia, Edge Effects, Edge and Surface Masks, Sharpening Toolkit, Split Toning, Tone Enhance, Tone Mask Toolkit.