I've used raw disk access under VMWare Fusion. It's less than intuitive, but it works. The helper app (and google-fodder) is "/Library/Application Support/VMware Fusion/vmware-rawdiskCreator".
Important: Consider this a "from-memory, basic idea of what the process requires", rather than a howto - please do google for "fusion vmware-rawdiskcreator" to find a proper walkthru if you choose to go this route. I can't promise my memory is accurate enough to trust your partitions to.
The biggest catch is that it won't find the partition unless it's been previously booted with Boot Camp, or you've used rEFIt's partitioning tool to sync the MBR. vmware-rawdiskCreator reads the partition list from the MBR, which isn't otherwise kept in sync with the GPT (bios partition tables vs EFI partition tables).
$ /Library/Application\ Support/VMware\ Fusion/vmware-rawdiskCreator print /dev/disk0
Nr Start Size Type Id Sytem
-- ---------- ---------- ---- -- ------------------------
1 1 976773167 BIOS EE Unknown
(disk0 is your first disk). If you get similar results to mine (one big partition type'd BIOS), you don't have the MBR sync'd with GPT. rEFIt (refit.sf.net) is my preferred way to do this, but bootcamp will do it for OSes it supports.
If you do get a list of usable partitions, you then need to create a vmdk (vmware's disk format) pointing to the right partition. This is done with
$ sudo /Library/Application\ Support/VMware\ Fusion/vmware-rawdiskCreator create /dev/disk0 n Filename lsilogic
Where /dev/disk0 is the physical disk containing the partition, 'n' is the partition number listed by the first command (print /dev/disk0), and Filename is what you want to call the resulting disk image.
You can then change ownership of the two files it creates (Filename.vmdk and Filename-pt.vmdk), and use them as existing disk images when creating a VM.
Not so straight-forward :) It does work tho; I've used this method to install linux on a machine that has a dead optical drive.