Tulio Campagnolo hadn't bargained on thieves when he revolutionised cycling with his wheel quick release. While not a security device, these Allen skewers will prevent opportunist tea leaves from whipping your wheels while you've stopped off at the supermarket for a few minutes. The gold test samples were a bit gaudy, but there's the option of black anodised or white powder coated finishes.
Offered in a choice of standard and extra long to accommodate both road and mountain bike spacing, they differ from cheaper models thanks to stainless steel tab nuts. These eliminate the need to hold the opposite end cap with a spanner when tightening/releasing the bolts, making them more convenient and surprisingly nice to use.
There's a 13mm cone recess should the cam fail, so you'll always be able to remove your wheels, and serrated nuts offer excellent purchase against frame/fork ends. However, while they have performed faultlessly on a geared bike, I would fight shy of pairing them with the stresses you get with a fixed set transmission bike.