What do you guys do when getting an art block or just in a rut?

I've been miserable the last few days because I have commissions to work on and personal project ideas and prepping for art market next month... but I set up my materials and I sit down and then I just sit, I stare at my tablet /canvas / paper etc and I just can't will myself to get to work.

How do you get past a funk? I want to do my art, I need to work on these things. I try talking to my partner and friends but they just can't relate very well, so perhaps a fellow art friend can?