Back then we used to make OVA images, which didn't attract any interest at the time and the idea was abandoned.
Perhaps it's time to do it again and gauge the interest. We made one for 1.1.7 and it's available from http://packages.vyos.net/iso/release/1.1.7/vyos-1.1.7-amd64-signed.ova and from the mirrors.
This OVA uses an embedded signature made with an object code signing certificate issued to Sentrium, to simplify deployment.
This one was made with VMware and uses VM hardware version 9. It should be compatible with ESXi 5.5 and later and VMware Workstation 9 and later.
Theoretically it may work in other systems with OVA support, but from my experience OVF, despite technically standardized, doesn't work that way. Please tell us if you've had any luck with it and if you know how to make it friendly to multiple systems.