Along with various dolphin sightings I haven't been able to pin down to a species, I have seen:
Common Bottlenose Dolphin (Tursiops truncatus) - Northern coastline of the Isle of Skye, near Staffin - 2010
Harbour Porpoise (Phocoena phocoena) - Numerous locations on Scottish and Northumberland coastline over the years.
Risso's Dolphin (Grampus griseus) - Numerous locations on NW Scottish coastline over the years.
Shortbeaked Common Dolphin (Delphinus delphis) - two definite sightings: on ferry between Mallaig and Armadale (Skye) in 2010, in Firth of Clyde near northern coast of Isle of Arran in 2011.
Minke Whale (Balaenoptera acutorostrata) - Numerous occasions in the waters around the Isle of Skye.
Sperm Whale (Physeter macrocephalus) - one sighting of a living beached whale, which died shortly after I arrived, at Beadnell in 2010. One brief sighting off the southwest coast of Skye in 2001.
And the sighting with which I am most pleased.... Cuvier's Beaked Whale (Ziphius cavirostris) - one sighting when on a boat off the coast of Skye, sailing from Elgol to Loch Coruisk, in 1999.