I’ve written about how much I love my Tom Bihn Synapse rucksack a couple of times before. I’m probably boring everyone stupid with my adulation, but I really can’t say enough good things about this bag. I’ve had it now for nearly two years, I use it every day, and it still surprises and delights me.

A couple of weeks ago, I had to take two bottles of champagne¹ to work. In case you’re thinking that the life of a biologist is a great deal more glamorous than you had previously suspected, this is certainly not an everyday occurrence. One of the PhD students who I co-supervise with a colleague was having her viva, so I wanted to get some bubbly for a bit of a celebration when she emerged, blinking, after several hours of grilling by the examiners.

Bottles are pretty heavy and I was travelling by train that day, so I wondered if I could carry them in my Synapse on my back, rather than in a bag held in my hand. Given that my Synapse was already filled² with a considerable quantity of stuff that I take to work every day, I seriously doubted that there would be room. I already had my MacBook Air in a neoprene case, an A5 notebook in a leather case, a pencil case, camera, glasses in a hard case, a couple of pouches stuffed with random odds and ends, a packable shopping bag, wallet, keys, a large pair of headphones, and various other bits and pieces in there. Two bottles of wine would be at least another 1.5 L of volume to fit in somehow. However, in the spirit of giving it a go, I unzipped the bag and shifted the contents of the main compartment a bit before trying to slip in one of the bottles. After a bit of jiggling, it slipped in comfortably. I tried the other bottle, wondering if I could pull off this magic trick again. The second bottle was swallowed by the bag. I zipped the bag up, not really believing that it had worked. As usual, the Synapse sat there insouciantly, looking as if it just contained a couple of notebooks and thin jumper. It was pretty heavy as I was hauling it on to my back (as you would expect), but once there, it felt very comfortable.

When I removed the bottles from my bag later on in front of an audience, it was with the smugly mysterious air of a conjurer pulling a brace of rabbits from a hat. I’m pretty sure this bag breaks all sorts of laws of physics, but it’s remarkably handy.