Sometimes, when I get really stressed, I just like to look at photos of knitting. And when I want to double that soothing power, I look at photos of lace. I can browse recent projects in Ravelry's Lace Knitter's group or I can search for lace on flickr. There's just something I love about the floaty, almost ethereal quality of lace. It calms me down and inspires me. Sure, it's time that I'm not knitting lace, but it's an okay trade-off. Maybe it's because you can't knit lace angry? Or being very distracted at all? Maybe it's just because it's pretty. Anyway, it works for me.
*Above photo is of my Seraphim Shawl knit in 2006 and gifted to my aunt for Christmas (rav & lj links respectively).