nailpolish, you have my sympathies. I am stuck in with one child today after a day of being stuck in yesterday. It is going to be a long day. Am thinking of wrapping up and taking ds on a needless bus journey just because he loves doube decker buses... how sad is that?
How about having a teddy bear/dolly's picnic for lunch? She could spend ages choosing her fave teddy's and dollys..making sure they're comfortable etc while you get some lunch and then put the rug out and have some fun.
After that while you're clearing up you could make a tent with two chairs and a long throw or rug and give her some teddy's and a torch?
You could do a messy picture? Cover the floor with newspaper and lots of white paper and let her put her feet in the paint and you can have lots pictures with her footprints - it's especially good fun if you put a cd on and dance away! Just remember to have a towel. She could help you do your little's one's feet and hands also?
Making pictures for friends and family? Or making an invitation for one of her friends to come for tea and then looking through the recipe books for something that she could cook for her friend?
Do some baking?
Sorry probably rubbish idea's. Will try and think of some more. Hope the day goes okay for you!