Synchrotech has announced the MicroU2E-MV USB to ExpressCard adapter, which allows ExpressCards with voltages of both 1.5V and 3.3V to connect to a USB port. The adapter can accept both ExpressCard 34 and 54 sizes and is cross-platform, bringing ExpressCard connectivity to Mac (and PC) laptops lacking ExpressCard slots. The adapter, which is limited to USB-based cards (and will not work with PCIe-based ExpressCards), is available now for $48 and requires a USB 2.0-based ExpressCard and a host computer running Mac OS X or Mac OS 8.6 and above (also Windows ME or later).
The adapter is geared toward ExpressCards that add wireless functions, like WLAN or cellular broadband (3G for example) and Memory Card adapters. It will not work with cards that add SATA, FireWire, Gigabit Ethernet or USB 2.0 throughput, which depend on PCIe architecture.