You can use a weber charcoal grill as a smoker by setting it up for indirect heat and managing your fire. It is difficult, however, to control temperatures and you will have to fiddle with it quite a bit to maintain temperatures for anything over 2 hours or so.
If you're interested in a low-cost charcoal smoker the Weber Smoky Mountain smoker (google it) is amazing. I bought it 5 years ago and it continues to surprise me with how easy it is to use. I can use it for cooking a chicken at 350 F or for warm-smoking sausages or cheese at 90F. A full load of charcoal will maintain temperatures at 250F for 18 hours or longer once you get the hang of it.
The WSM has similar durability as your wife's office's weber grill as well.
I'm a bit of a fanboy as you can tell. More info available at
www.virtualweberbullet.com and the associated forum.