Microwave friendly utensils, what qualifies as
Here is a set of guidelines I found from a major manufacturer: http://www.geappliances.com/search/fast/infobase/10001216.htm

As you mention, any metal items or items with embedded metal are not appropriate.  Thinner and bendable plastics are probably not a great idea either since they can melt.  Most ceramics and glass should be okay.

When in doubt, check to see whether the item is labelled as microwave-safe, and if you can't tell, test it first using the method described in the linked guidelines.