The most venerable of spirits :-) But why oh why is it called 'scotch'????
What's the difference between whisky and whiskey? Apparently the original spelling was 'whiskey' but unusually for the (British) English language (as opposed to US English), the accepted spelling came to be that without the 'e'. Now the distinction is that 'whisky' refers to Scotland's version while 'whiskey' refers to Irish and American whiskies, thought it's definitely not a hard-and-fast distinction. (See the Wikipedia entry on whisky.)
I may have sampled one or two
Laphroaig (pronounced La-froyg) No Half Measures here!!! A personal favourite: the 15-year old is truly excellent. Will have to get to Islay someday...
United Distillers produce some very fine single malts too, most notably the range of so-called 'Classic Malts'. Talisker, Lagavulin, Dalwhinnie, Oban, Cragganmore, Glenkinchie.... just the names are enough to make me want to go home now and start sampling :-)
Glenmorangie Fabulous single malts, especially the 18-year old. Wow.
Balvenie Another personal favourite at 10 and 15 years old. What comes to you as the 15-yr old originates solely from one cask.... Then I discovered the sublime 25-year old...
Edradour A relatively recent discovery, this is unlike any other malt I've tried. Stunning.