I googled Groundskeeper Willie in hopes of finding a clip of him in the one-man-band getup performing "I'm a Maniac," but found this audio clip instead, which is one of my all-time favorite quotes from the show:
I also found this article, which is worth reading in its entirety, but here are a few notable paragraphs:
Americans don't know much about Scotland and what they do know is mainly bad. Should the Scots be worried?
Forget Sean Connery, Ewan McGregor, Rod Stewart or even Scottie from Star Trek - for many Americans, Scotland is summed up by grumpy, aggressive Groundskeeper Willie from The Simpsons...Despite all the promotional efforts, research funded by the Scottish government finds Groundskeeper Willie is the character most Americans associate with Scotland.
But as regards the rest of it - the Groundskeeper Willie characteristics of undue aggression, grumpiness and testosterone - why fight it?...Fighting for your right to party is in with the bricks in Scotland. Clan chiefs originally owned no land, but were judged by the number of fighting men they could summon at times of war. Urban gangs seem to operate the same warped code of honour. But then so do the Tartan Army - repeatedly voted the best football supporters in the world because of their discipline, good humour, ability to get on with host nations and evident pride in not behaving with the enduring neddishness of some England supporters.
If Americans can't name any Scottish cities, this reflects badly on the inward-looking, self focusing nature of their own society. Elsewhere in the world Scotland punches well above its weight, thanks to the Edinburgh International Festival and its Hogmanay celebrations. And scarcely a week goes by without Glasgow - despite its all too evident problems - bagging another international accolade. This month, No Mean City won the best marketing award from the International Congress and Convention Association this year. Eighty countries voted for that - but duh! - doubtless the Americans know better.