Ideative has launched SD memory cards with built-in USB connector, removing the need for a separate flash memory card reader. The cards mimic the look of normal SD cards but have a cap that can be pulled off, to expose the USB connector.
With the cap off you can plug the SD card into a USB port. The card uses USB 2.0 and this results in high data transfer speeds of maximum 10MB/s. In The Gadgeteer's tests the card copied files from the PC to the device at 4.6MB/s and transferring them back was done at about 6.75MB/s.
Currently it is only available in 128MB capacities. Read more at The Gadgeteer