We've noticed a growing trend for sleeping outdoors, albeit in style. Hotels are putting wooden bothies in their grounds for nature-loving guests, bush survival courses are experiencing a surge in popularity and you can sleep in the treetops in Cornwall (www.mighty-oak.co.uk), or hammocks strung up in the rainforest canopy in Borneo (www.discoveryinitiatives.co.uk).

These are all good options for the modern tree-hugger, but none are quite so pleasing to the eye as the Free Spirit Sphere. These nest-like spherical pods are made from laminated wood and hung up in trees with a web of ropes connecting them to any strong points available.

Two spheres, Eve and Eryn, are available for rent in Canada, at Qualicum Beach on Vancouver Island in British Columbia, and the owner hopes to eventually have 15 there as a spiritual retreat.

Eryn has a double bed, cupboard space and counter, settee, sink, microwave and refrigerator. Eve is more spartan, with just a bed. Both have insulation, with bathrooms nearby. You don't have to have the climbing abilities of a monkey to get inside; a spiral stairway circles the tree trunk to a short suspension bridge leading to the door at the top.

To book, contact Free Spirit Spheres (00 1 250 757 9445; www.freespiritspheres.com). Eve costs from Can$100 (£44) a night or $175 for two nights, Eryn is $150 a night, $275 for two nights ($35 extra a night for a third person in a loft bed). You can also buy ready-made spheres for your own garden, from $45,000 in fibreglass, $150,000 in wood.