I saw this on an infomercial. It looks pretty awesome, but the price tag is pretty steep... it looks like it operates much like a bone saw, but it slices through wood, grout, nails... etc. I wanted to get a good review on this product prior to buying it. Has it been on the market for a long time? 400.00 is a lot of money, but if it does what is says it can do, it may be worth it.

Rockwell has one they offered me for about $110, can't say about quality comparison or quality and amount of parts for both.
Here's the Dremel, maybe at Home Depot:
http://www.dremel.com/en-us/Tools/Pages/ToolDetail.aspx?pid=Multi-Max

For Comparison, Here's the Rockwell:
Rockwell Tools - Save When You Buy Direct from Rockwell (http://www.rockwelltoolsdirect.com/sonicrafter.php)
And the Multimaster:
https://www.4multimaster.com/default.jsp