For thermometers, I have been using an Atkins 330 digital thermometer:http://www.arrowscientific.com.au/Atkins_330.html
It has a waterproof probe and has been working flawlessly for over 5 years. They are prohibitively expensive new, but if you watch ebay, they come up once in a while and you should be able to get it for somewhere between $30 and $50. If mine ever stopped working, I'd get another without question.
As far as hydrometers go, I was super bummed when I broke my Brewers Edge Precision hydrometer from Williams Brewing. Make sure you look for the word "Precision" because the one without that word doesn't look all that great. They were out of stock up until recently, but I just checked and you can now order them again. I'm going to order my replacement now.