I veer more towards traditional toothbrushes, but my partner likes his electric toothbrush. I'm intrigued by this Sonicare product that's been mentioned a few times so far in this thread.
As for me...
Full-day jeep safari in Nepal, 2014. Just me and my partner, a driver, and two guides. Can't remember if it was charged per person or a flat cost for the one jeep, but anyway it came to around $200 with tips, so my share was about $100. Amazing experience, would do it again if I go back to that part of the world. Our guides were friendly, spoke good English, had a keen eyesight for spotting wildlife, and were knowledgeable about the different species we encountered. They also seemed just as excited as we were to see the animals, even though one might think that they are used to it, and I love that!
Vibram Five Fingers. I have two pairs and actually got them for quite a bit less than $100 per pair (once on eBay and another time with a Groupon deal), but whatever. Thought I was never going to walk long distances again without suffering due to bunions, even in shoes that regular people would find comfortable. I saw a podiatrist and had expensive custom orthotics done, and they helped, but I think my VFFs are even better (and cheaper, too). At one point just walking >30 minutes around the neighbourhood would end up in pain, then I got my VFFs and I started walking everywhere again and I felt like I had my life back. I even wore them trekking in Nepal, several hours a day for several days straight, no problems! Bought in 2013, no need for replacement yet but when the day comes, it would totally be worth it to purchase again.
I also really like my Sunbeam stick blender, though again I'm not sure if it counts - I think the full price would have been $100, but technically I didn't spend $100 on it because it was purchased for about half that on special, and in fact I didn't spend any money on it at all as it was bought for me as a gift. I make smoothies with it all the time, occasionally soups, and it's so easy to clean. Got it in 2012.