When I lived in Bristol I learned Scottish Gaelic (you'd be surprised how many Gaels there are in Bristol!), or at least enough to have a blast at a decent conversation with someone, though I am now getting very rusty with it! I've also dabbled in Irish, mainly Ulster Irish which is similar to Scots Gaelic. Whilst I am not completely fluent, and much better at reading it than speaking it, I remember the day when I suddenly realised I was getting somewhere with understanding it. An episode of Hamish Macbeth was on the BBC and two hard men from Glasgow were trying to intimidate the locals in the episode at the village pub. Two old gents sitting on a table were completely unphased and spoke to each other in Gaelic. The first turned to his friend and said "Tha iad gu math boidheach". The reply was "Oh tha, tha iad direach abaich"! It wasn't subtitled, and I nearly wet myself laughing - "They're well beautiful", "oh aye, just ripe"! I know who I'd have been more intimidated by!
I've always loved trying to get to grips with the language, and whilst I know of two ways to ask how somebody is in English ("How are you?", and the more proper form in Ulster English, "What about ye?"!) Gaelic is much more fun, with many different ways to ask the same thing depending on where you are from! Here's a smattering...
"Ciamar a tha thu?" Textbook Scottish Gaelic!
"De mar a tha thu?" Western Isles
"De man a tha thu?" Western Isles
"Cionnas a tha thu?" Sutherland
"Cad e mar ata tu?" Ulster
"Goide mar ta tu?" Donegal
"Conas ata tu?" southern Ireland
"Kys t'ou?" Isle of Man
They all say the same thing, and they are all corruptions of the same words, but each area has mutated the greeting in a different way. Written down they all look similar, but their pronunciation varies quite dramatically.
Here's a few thank yous also...!
"Tapadh leat" - most of Scotland
"Gun robh math agad" - Islay
"Go rabh maith agat" - Ireland
"Gura mie ayd" - Isle of Man
If you have Gaelic speaking ancestors and want to learn the lingo, don't just grab the first Gaelic book you can find - try to find something that will help with the right dialect of Gaelic that is relevant to your ancestry. BBC Gaelic today tends to be heavily influenced by the Western Isles where the language has survived the longest, and where most of the BBC's Gaelic department staff come from, but there is quite a difference between an island dialect and that of Perthshire, where it is all but extinct now, for example. There is also quite a difference between the Gaelic of Lewis, which is almost Irish in its pronunciation, and its neighbour of Harris, technically on the same island but a world apart linguistically!
Now You're Talking is a great fun way to dip into Ulster Irish, available from Amazon at http://www.amazon.co.uk/Now-Youre-Talking-Multi-media-Beginners/dp/0717123499. Speaking Our Language is the equivalent series for Scottish Gaelic (www.smo.uhi.ac.uk/gaidhlig/ionnsachadh/bac), presented by my old boss at STV, Rhoda MacDonald. Both are 'parrot fashion' learning courses so you will need to source more formal texts such as Boyd Robertson's "Teach Yourself Gaelic" (for Scottish Gaelic) to get to grips with grammar, but hearing the language spoken is half the battle.
Have fun if you decide to go for it also - you won't regret it!