Mental constipation has long been the bane of any writer's life. There are times when the words flow so swiftly we feel we can't keep up. Then there are days where we feel we need a mental enema to unstop us.
Sorry, hope you weren't eating when you read that.
Personally, I have a bunch of different things I do when I get hit with writer's block. The first, and for me the easiest, is I switch to another project. I usually have a minimum of five projects going simultaneously at any given time. Sometimes, switching to another project helps get my mind flowing.
Another thing I will sometimes do is take a break. Go work out, read, watch TV, whatever. Sometimes, block is my brain's way of saying, "Enough already! I need a time-out!"
Since I also love Tarot cards, sometimes pulling out a deck and playing with it for a while will help jumpstart the brain. I love the archetypical images on the decks I own, and sometimes seeing them laid out will give me ideas, or at the very least help clear my mental palette for a while and allow my brain to focus on whatever the issue is.
Jumping to another scene in the same book will also frequently help me.
What will work for you? Only you can decide that. Here's list of links, some funny, some serious (some both) with information that's helped other writers.