The Neville Brothers are a bunch of BIG American guys (brothers) who sing like angels. I was on an airplane with them once (that's just my 'brush with fame' for the evening). They've made plenty of recordings but apprently are MUCH MUCH better live.

I imagine a lot of the Mardi Gras stuff you'll find on the web is about the Gay Mardi Gras which happens annually in Sydney and is one of Australia's biggest tourist events. It's never held on Shrove Tuesday, or indeed any Tuesday.