yep, your plant is sending out what is commonly called air roots. if they come in contact with soil, they will root and you will have a secondary plant.

just don't wanter it more than you water the mother plant. if you do, it'll rot instead of growning. it might shrivel a little, but it'll be ok.

Hrm..I only water my plant about once every 2 weeks.

I read this in "The Guide to Houseplants" by Maggie Stuckey, illus. by Tamara Durbin Brown. Exact quote: "...jade plant will tell you when you're making a mistake. With too much water, the plant will put out white, spiky-looking roots about one-quarter inch long at points along the stem. That's your indicator: cut back on watering." I've found the info in this book to be quite accurate thus far.

Of course over-watering does lead to root and stem rot, but by the time that happens it's usually too late to save the plant. My take on the above quoted passage is that it implies that Jade has an early-warning symptom of over-watering, which can be corrected.

Every 2 weeks doesn't seem like too much, but there are so many variables...pot size and material, soil material, season, humidity, etc. ...that effect watering frequency. I was thinking humidity might be the issue...I have a Swedish Ivy that put out a lot of long aerial roots when outdoor humidity was over 80% and I had the windows open..I reduced watering, even though I wasn't over-watering by my schedule, and the plant did (and does)fine with that.
Jades do prefer low humidity, and if your humidity is high can do with even less water.