What's more than five metres long, powered by a diesel engine, converted from a van and costs more than £50,000 - yet is now a dead cert for a place in my dream three-car garage?
If you've ever owned or even spent some time in a camper van, chances are you've jumped straight to the answer and are nodding your head in knowing understanding.
If you haven’t, chances are you're wondering instead if the frost has seized my brain. I’ll admit now that there was a time that I too thought that paying a huge sum to lug your bedroom (and kitchen) around with you was absurd.
But then I spent a week with the family touring the south coast in a Mercedes Marco Polo, which I started off viewing as an impressively transformed V-Class and now look at like a heart-broken teenager saying goodbye to a holiday romance.
Across a wind and rain-swept week, the Marco Polo got under my skin for a multitude of reasons, not all obvious, and not all ones that I'd encountered in my motoring life before. I always thought dream garages were the sole preserve of supercars and high-end SUVs. No more. That Lamborghini can wait for the second lottery win.
If the motor car brought the world freedom of movement - a point that needs sharp reflection in a world that is both increasingly environmentally aware and consequently anti-car - so it is that the camper van is one interpretation of its no-compromise end point.
Sure, we didn't exactly park up in lay-bys and make our home wherever we fancied (confession time: on some nights it was so cold that we even rented a static caravan), but what we did find is that we had what we wanted when we needed it. We had space to pack everything, we had food and hot drinks on hand and even the space for a quick mid-afternoon rest if it was needed.