M-Systems today announced the DiskOnKey Pro, the latest addition to its DiskOnKey product line of USB keychain storage products. Based on the original DiskOnKey design, the new device enhances the line by offering the same storage capacity only in a form factor half the size of the original design. The DiskOnKey Pro will initially be available with storage capacities of 16MB (US$34.99), 32MB ($44.99), 64MB ($69.99) and 128MB ($114.99), with 256 and 512MB capacities expected soon.