Spent Grains from home brewing: anybody used them before to bake bread?

You could dry the grains so they could be ground. If they are sprouted, then you have a malted flour. Without yeast from the brewing it can be used to promote good rising in yeast breads.

Chef Lydon's mention of pancakes and Helen's mention of beer cheese soup gave me the idea for maybe cheese fritters made out of the grains. Chemically leavened if yeast fails you here. They will probably be nice with beer, too.

Wow, you have been busy, and all your creations sound wonderful. Melissa Clark's soda bread recipe is golden, and I imagine it was excellent with your grains. I'm looking forward to trying a cracker formula. Good on you! Most of all, it sounds like you're have a whole lot of fun.

Shuna, is this the recipe? Looks like a good adaptation. I can't find a copy of Ana's book-- but I might give this a try:
http://foodieinberlin.com/2011/08/07/sumac-quinoa-lavosh/

I've used them, too, with success. I just add about 1 cup of the grains to a normal recipe that yields 2 loaves of bread. Haven't made any in a while. I ended up freezing 1 cup portions of the grains for the purpose...
Have fun with it! hmmm, I feel a cheese beer soup with croutons made from the grains....

Boulangere, I do have a thermometer and lots of baking equipment- so that isn't an issue. All the loaves I made had been taken to 180 or higher. (I made three: one that was a yeasted boule, one that was a heavily yeasted boule (I tripled the yeast), and one that was soda bread). I also made a foccacia. Last night, I started again:

I added 1/4 cup of spent grains, (passed through my food processor but still wet) to a whole wheat Irish Soda bread recipe from Melissa Clark. It worked and I loved the way it tasted. Malty, but still cooked through. I upped the baking soda and kept the full amount of yogurt. It tasted lovely with KerryGold salted Irish butter. My beer making holiday house guests approved of it.

I also made crackers, using this recipe from 101 cookbooks that calls for cooked oatmeal. http://www.101cookbooks.com/archives/oatmeal-crackers-recipe.html
I subbed the spent grains, (still hot from my husband's brewing process) for the oatmeal. That worked very well, too. It was impossible to knead, so I ran it through my pasta machine instead. I used the ravioli cutter to make the crackers. I added a fair amount of Rosemary and Maldon salt. Tasted excellent and I'm saving them for New Year's Eve.

Pancakes are definitely a possibility, though I'll have to wait until tomorrow when my husband and his buds are making more beer. Porridge would taste great, but given that the grains are now almost 100% insoluble fiber, I'm thinking that it is not a good decision for the digestive tract. I had a bit of a stomach ache yesterday after trying so many breads/crackers with spent grains and I would not want to inflict that on anyone!

There's an amazing "Lavosh" recipe in Anna Hansen's The Modern Pantry cookbook that employs any and all cooked grains you have on hand.

My own experience with this sort of thing is that the grains I was given from beer making were a bit dry and spent and were interruptive in my bread (I made yeasted & naturally started bread.)

How about turning them into porridge? or putting them in pancakes/muffins?

Interesting question. Perhaps you could try developing some flatbread recipes instead, and see if they yield a successful crispy -chewy result.

Boulangere, I'm actually getting these grains before the yeast has been applied. My husband likes to add the yeast to the wort, after the grains have been removed. So the grains don't have yeast.

My problem so far is the opposite. I am struggling to get the dough to rise and struggling with a very gummy texture after baking.So far, I've only managed to make a half way decent foccacia.

Yes! There was a thread about this very subject a while back. A good friend and excellent brewmaster gives me spent grains whenever I need some. They're outstanding in bread. One hint: be sure to bring them just to a boil before adding them to your dough. That kills off yeast spores that would otherwise WAY overproof your bread. Then rinse in cold water, drain, and off you go. I've used them often here: http://www.food52.com/recipes/10683_power_bread. Use it in place of the 3 grains, in the same quantity. You'll very much enjoy baking with your grains, and have some good beer to boot. Lucky you!