A sofa bed performs the function of a couch for a room whenever it is folded up with the bed portion tucked into the sofa. Many sofa beds can be covered in the fabric of your choice, meaning the piece doesn't just have to be perfunctory, but it also can be a decorative furniture piece for your room. When folded up, no one can tell it has a sofa inside; it looks like just another regular couch.
A sofa bed works well as a guest bed in a space where you don't have the room to fit a full bed year-round. You can place a sofa bed in a room like an office where you want the main function to be the office setting but want the flexibility of extra sleeping space once guests arrive. Pulling out the sofa bed and dressing it with bedding and nice pillows will make it look like the room always had a bed in it.
If you do your daily exercise in front of the television using a workout video, you can use the pullout sofa as part of your stretching routine. Pull the sofa bed out, and sit on it to do leg lifts and to stretch out your arms and legs. The soft cushion is also an ideal place to do Pilates, particularly if you pull the mattress onto the floor.
Little ones often enjoy using household furniture for their playtime, and a sofa bed can working nicely just for that purpose. Pull out the bed in the sofa, and drape sheets over the bed so that the fabric hangs over the sides. It will work as a makeshift fort, which can be packed up afterward for easy cleanup.