Spare bedroom to use as something else?

[Rarily]

Our house is four bedrooms. We have on DD and I'm now feeling that having a kingsize bed in the spare room (other room is used as a study) is a bit of a waste of space as we don't have visitors very often. I'm thinking of getting rid of the bed and getting a couple of fold up mattresses to be stored and taken out when we have visitors (elderly / VIP visitors will get our bed, otherwise people can use the mattresses.) Has anyone done this? Any ideas how can a bedroom be used other than study? Any recommendations for gold up mattresses?
Thanks!

We're buying an Ikea Hemnes day bed for our fourth bedroom. It's a sofa but can be used as a single or double bed when guests come over. You wouldn't have to offer up your bed if you had this or something similar and could use extra room as second sitting room/ craft room/ library/ gym etc.

I long for an extra room that i can just line with shelves and storage that is accessible and organised so that my home can be clutter free but my things dont need to get shoved into the loft to be out of the way.

how about a playroom? and I second the ikea daybed I long for space for one of those!

We're making our spare 4th bedroom into a games/chill out room with a sofa bed, tv on the wall, dvd player and all the Xbox/play station/gaming stuff there, DH wants to put a mini fridge in there too. He will prob go up there to watch sport, DDs will play games in there and I'll prob only ever go in there to clean it

Of our 3 bedrooms two are spare (DD is still in with us) so one is a dressing room (wardrobe, chest of drawers, single bed with drawers) that can be a guest room if needed. The other one is a box room at the moment as we're moving soon.

Arguably if you can't think what to do with the extra space, there's not much point making it! I would have a library or craft room.

We have a single bed with a 2nd that is stored underneath, so there is always a proper bed but it doesn't dominate the room.

Thanks all - lots of ideas!

I would make it into a workshop/art room where I can leave my projects undisturbed on the table when I have to abandon them to go and cook or to work

My kids however would love to have music room to have all instruments in one room.

We have a spare spare room that functions as a drying room in winter. I've got four drying racks in there and have no need of a tumble drier.

How old is DD? Perhaps wait a while and then see what might work best. We have a downstairs 'spare room' that has a sofa, TV and beanbags and as DS gets older I can see him using it to have friends round whilst we still have a 'grown up' sitting room.

Your DD might end up wanting a music room, dance studio, library, craft room, play room, chill out room...

It sounds as if it's fine as a bedroom just now, you could hang on until you know what you might need.

Thanks again for all the ideas!