Cook a meal in your pajamas. There is something romantic about preparing a meal together. It doesn't have to be gourmet or fancy. A messy meal makes for more play. If you get carried away, no worries about ruining your clothes, you are already in your pajamas.
Explore new or familiar terrain. Get some body crayon and make a map of your partner's favorite places. Be an explorer.
Make it a movie night. Redbox movies are only $1 a day. You can also find some good deals at your local thrift store. Don't forget about free videos at the library. Grab a bag of popcorn, some strawberries, a bowl of grapes or whatever your favorite snack is.
Make something together. Take a trip to the local craft store and find a project you can collaborate on. Wear old clothes get messy and have some fun making your new creation.