Hey I found a pretty cool exploit while on my priest. First of all the Add-On "Inventory on Par" is needed. What this mod does is give a number score on a players gear. If you double click a same faction player then it shows you there gear and there IoP (Inventory on Par) score. The mod also saves there gear to your database and you can look at a players gear that you inspected weeks ago when ever you want.
Download Inventory on Par -> Download v7.60 | World of Warcraft @ Curse.com
Now for the exploit...
On my priest I was going to herioc hellfire ramparts and there was a horde at the stone, I decided to Mind Control him and throw him off the ledge, but when I mind controled him I noticed IoP had logged something to my database (which can be accessed from titan panel, FuBar, or mini map icon). And I noticed the horde's name had been added to my database, I clicked his name in the database window and it showed me his gear as if I was inspecting a member of my faction! So I found another horde, tried again and it worked again. I don't know if this will work with the Engineer's Gnomish Mindcontrol Helmet but its worth a try!
Easy Steps:
1) Download Inventory on Par (link above)
2) Mind Control a horde.
3) Double click him/her while mind controled.
4) Click your Inventory on Par database.
5) Click the horde's name that you mind controled in step 2.
6) IoP will show all their gear, compare it to there level and give a # rating.
Inventory on Par is also used in my guild for raids. For example my guild set a minimum of 250 IoP Rating to get into a Karazhan run, 450 IoP for Gruul's and Mag's, then 550+ for SSC and TK: The Eye. It also tells you how many points each piece of gear is worth so you can figure out your worst piece of gear (which was helpful when I first hit 70, I could find my weak points in gear and work on them before I work on my stronger points).
Hope this was helpful, and if someone tries with Engineering Helmet let us know how it goes, I am interested to see how that turns out.