I have to agree with giving her scissors! My 3 1/2 year old daughter will sit so happily at the table with scissors, construction paper, and a glue stick. Just be careful to make sure she's not having too much fun. One night when I took my daughter's ponytail down, pieces of hair were falling out...she cut it! That was a few months ago and she knows better now. Luckily, you couldn't tell where it was cut unless you knew!
You could also try magnetic letters and a magnetic dry erase board. My daughter loves playing with the letters or other magnets on a dry erase board or on the refrigerator.
If the weather is nice and you want to go outside for a bit, maybe she could "wash the car", water the grass, or even plant some flowers. The water hose is another big hit around here.
If you want to make a big purchase ($200) for a little bounce house, then you can get one at Toys R Us. It's quick and easy to set up; and my daughter (and the neighbors) love it! It's been a great investment. My 10 month old son loves it, too...but I only let him in there when it's just my daughter and him, for safety. Anyway, for us, it was a bargain. We've used it so much!
You might also want to "cook" or "bake" with her. Maybe some easy cookies from a mix...or she could put the frosting and sprinkles on some cupcakes. You could make milkshakes or slushes in the blender. Or make ice cream sundaes together with the whipped cream, sprinkes, and all...
You could also do a photo shoot and maybe let her take some pictures of the babies...they may not turn out like your pictures, but with a little help, she could take some cute ones and have some fun. She'd probably be really proud of herself, too.
If you dare, you could give her a hairbrush and some hair things and let her do YOUR hair!
Good luck and have fun!