Things you don't want to see while driving at 100 kilometres per hour down a major highway in Tasmania: a humongous Huntsman spider running around the dashboard of your car.

I had several adventures with these spiders when I was living in Western Australia, but had not expected to find them in Tasmania’s cooler climes. I try not to kill them, because they are useful beasts that eat bugs, and if you whack them they leave blobs of spider nougat all over the place. They really are big; an adult female would cover a salad plate from toe to toe. They are interesting creatures—in the right place.

So there I am beetling along on a downhill slope when the spider comes from nowhere, leaps over the passenger headrest and lands on the dashboard. She stops to get her breath in her primitive book lungs, then starts towards my side of the car. What to do?

Tap brakes, put on signals, pull into breakdown lane, lower all the windows, and slide out carefully onto the road. Traffic whizzes by. Run around to the passenger door. Spider scuttles up onto ceiling of car, I use a shopping bag to chivvy it out the window. Run back to driver's side, slide into seat, hit 'close' buttons on windows. Frustrated spider scuttles back and forth trying to get back inside. Drive away happily thinking spider will blow off soon.

Get to Hobart, slow down to drive through city to reach appointment. Stop at red light, spider runs across windscreen--fortunately outside. Get to a parking space and sit in hot car for a long time before daring to leap out and feed the meter. Check for spider. No spider.

Have meeting, return to car, check for spider. No spider.

Drive to Kingston, do shopping, come out to stash bags in back of car, open hatch: Argh! Spider folded up in the flange of the door. Ill-advisedly try to move spider; spider moves into the car and inserts self in the slot that holds the seat belt. (Get strange looks from man in next parking bay who hears me muttering "Get away you bastard!") Stuff rags into slot of seatbelt and drive home looking in rearview mirror constantly.

Reach home after a nervous 40 minute drive; pull out seat belt--no spider. Spray seatbelt with bug spray, let it snap back, shut door and cross fingers.

Check next morning and find dead spider in back deck of car, belly up. Sorry, spider, but it was you or me--or both of us if I'd driven into a bridge abutment when taken by surprise some day.

Somebody has probably crunched the numbers to determine what size a spider in your car has to be before you panic at the sight of it. I could have tolerated one of those little striped grass spiders, or a tiny jumping spider—but the gigantic Huntsman with its velcro feet? No, sorry: I’ve got curds and whey to protect.