Arias Pistons 12.5:1 Compression 82mm Bore Honda B-series on 2040-parts.com

Which car has the best residual value? A MINI

The MINI has the lowest depreciation of any car in the UK When it comes to buying a car, many of us decide how much we can afford to spend and then go and look for a car that fits our budget. But what we should really be looking at is how the car we want will be worth in the future – its residual value. Because the residual value of your car is often where the biggest costs lies, and it has a major impact on monthly payments if you decide to acquire your nice new car on a contract hire or leasing deal.

Opel/Vauxhall RAK e concept

Opel/Vauxhall has released images of the RAK e concept prior to its unveiling at the Frankfurt motor show next week. Billed as a car that ‘could revolutionize urban transport', it's clear that the company is thinking along similar lines to Volkswagen (Nils) and Audi (Urban Concept). Frankfurt's shaping up to offer a feast of these new single or tandem seat concept vehicles that conceptually sit in between a scooter and a small car.

AutoWeek office swag: Mazda rotary-engine keychain with realistic motion

When I got the keys to our long-term 2011 Mazda 5 last week, they came with a surprise--this aluminum-and-brass keychain in the shape of a rotary-engine housing, complete with moving rotor. The rotor doesn't just rattle around or spin in a circle. Thanks to a thumbwheel on the back of the housing, coupled with a timing gear and offset crank journal, the thing actually moves in an approximation of epitrochoidal motion just like a real Wankel.