Finnien,
Gravity's Rainbow
I had no idea when I first picked up this novel about its reputation - perhaps this attitude helped. Also it was the first and only Pynchon that I've had time to read.
I devoured it. Probably in less than a week. Absolutely loved and adored it. Definitely in my list of top 10 or even top 3 books of all time.
I can understand that it may not be to others taste and it does tend to polarise opinion quite dramatically, so it's difficult for me to say, 'well, if you like Author X and Y, then you should definitely read Gravity's Rainbow' (not that my list of favourite authors will really have a bearing on this, for example I struggle somewhat with Ballard - an author that was mentioned in the thread you've just posted.)
Sometimes you just have to jump into the deep end and swim! It's exhilarating