Linux remote swap space

[sertys]

I've built an array of cloned VMs with differencing storage, running Linux and Windows guests. Recently i saw that my linux hosts are bulging in size despite very little disk space being used on them.
Then i ran top and could see that i was having 300-600MB of swap being used routinely on them. This leads me to believe that this is being written to the differencing disks as it changes(which with swap is constantly).
Has anyone figured a solution to move the linux swap to a remote physical drive so it's both faster and less space consuming? I know that swap over NFS is both unsupported and unreliable, so i though of shared folders.
Are they a viable option or i would look into iscsi or other lower level networked filesystems?