Via its Facebook page, the Hilton Malta is offering stays for two people, including breakfast, for just €99 a night.
The offer is available for bookings up to 28 February 2014. The saving you will make obviously depends on the applicable rate for the night you book, but it’s certainly a substantial discount (the lowest price I found in February, including breakfast, was €170). By all means compare it to the “market” rate on the Hilton website before you book.
To take advantage of the offer, you need to “like” Hilton Malta on Facebook, and then “claim” the offer from their Facebook page. You then book at the “claimed” rate by contacting the Hilton reservations office on +356 2373 3645 or firstname.lastname@example.org.
I have no reason to think that you would not also earn Hilton HHonors points on these stays.