I posted this previously but there's a problem with the images in the original post.
A different design with essentially the same results.
"I came up with this idea a [few] years ago.
Less than $20 invested.
The following is how I cold smoke inside......
A stainless steel colander flipped over the target helps concentrate the smoke if needed.
My vent hood doesn't vent to the outside, I open the window and use a box fan.
From my old blog.......
"Small Batch Indoor Cold smoking."
"I spent several weeks looking for a reliable and inexpensive way to do indoor cold smoking.
I settled on rolled cigarettes (LOL) heated with a soldering iron because it’s possible to smoke with pure tea leaves, herbs, sawdust, etc. without the fuel burning up too rapidly.
I invested about $20 in the cigarette roller, papers, soldering iron, spring and clamp."
"Below is some rosemary being rolled."
"Applewood smoked butter, rosemary smoked foccacia, tea smoked hard-boiled eggs….the possibilities are endless."
"The cigarette must be able to slide freely inside the spring. The soldering iron raises the temperature inside the cold oven only about 10 degrees above room temperature. Each cigarette smokes for about 30-40 minutes. A vent hood is recommended. My vent hood doesn’t vent to the outside, but that wasn’t a problem with a window open and the ceiling fan running. 
It's habit forming!!!!!""
