OCZ has introduced a new flash drive to their hardware lineup, this one a “Crossover” USB flash drive that contains both storage capacity and the ability to read from other cards. The new product, which comes in capacities ranging from 2GB to 8GB, plugs in via USB and integrates a microSD adapter on the chassis to plug additional cards into. The very small profile of the device makes it no more cumbersome than what you'd expect from a flash drive and the idea is that the card reader integration will reduce the need for multiple devices in a laptop bag.
MicroSD is fairly popular on newer devices, especially PDAs and many cameras, so OCZ at least picked the right standard to support. The actual demand for such a “combo” device could be debated, though, as most laptops already include card readers and most devices that support microSD can plug into your machine anyway. Regardless, it's now available.