This has been one of the features that never seem to have made it to VMware products such as Player and Workstation; The ability to boot from USB. Well with some 3rd party magic this is possible
Using Plop Boot Manager all you need to do is boot from the provided floppy image or CD image and this gives you a pre boot environment that can be used to select the boot device of your choice.
This is all possible because the plop boot manager has a built-in ide cdrom and usb driver to access that hardware without the help/need of bios. You can boot the operating systems from hard disk, floppy, CD/DVD or from USB. You can start the boot manager from floppy, CD, network and there are many more ways to start the boot manager
Plop Boot Manager 5.0 – Download