First are the Snap Circuits SC-300
which is good for the budding 8-14 year old engineer on your list that loves electronic projects. Another good toy for this age group is the Air Hogs Havoc Heli 
which is described as "the Smallest and Lightest Micro R/C Helicopter in the World." A number of guys seem to like this LEGO Mindstorms NXT 2.0 
which is a building kit (though a bit pricey) that lets a kid construct robots that see, speak, feel, and move. And finally, for boys, there is always the old standby, The Dangerous Book for Boys.
You can hear our interview with the author, Conn Iggulden, here. If you have other holiday gift suggestions for boys, drop them in the comments.