Designate each guest a room and get them to bring a basket, box or container filled with goodies that be of use for that room. This allows the guest to give a gift that will be useful for the bride and groom.

Decorations
Place baskets all over the room filled with nibbles. Use boxes to sit on.

Invitations
Use a piece of card with a small hole in the top and thread through a piece of ribbon so that it looks like a gift tag. Write on what room that person has got to fill a basket for. Leave enough space for the person to write the contents of the box onto it and then they can attach it to their gift.

Gift
bedroom - candles, silk pillows,
kitchen - detergents, recipe books, cookie cutters,
bathroom - laundry basket filled with soaps, shampoos, towel set,
lounge - ornamants, small pictures,
or a picnic basket filled with items used for a picnic.
Thses might sound like strange gifts to give but they are useful and they won`t break the bank.

Games and activities
Play treasure hunt where the guests have to find an item in each room and the winner recieves a bottle of wine.

Favors
A small basket of pot pouri.