DFS - Yes. Advertised on Fight International.
ASA - Yes. Advertised through website and e-mails sent out.
Nav Canada - Yes. By personal reference.
Abu Dhabi, Dubai, Oman etc. - Yes. Always accepting applications.
Airways - Yes. Not sure where it has been advertised recently, but looking for experienced controllers.
Swiss Control - Yes.
NATS - Yes
The list goes on.
Shortage - definitely yes; what are the ATC service providers willing to pay to attract??