Else 4 weights
Handsome 4 weights
Morphica 2 weights
Panoptica 7 styles; 3 weights of sans
(The last three are mine.)

Mantika Sans 4 weights

Buivenga's Delicious and others: http://typophile.com/node/77895

Delicato

Oops! No!

Not that you need my permission or anything, but: if all the characters in all the three weights of Benedictine Pro (including kerning) take up exactly the same width, then it is indeed what I'd call uniwidth. One thing that's not clear in your text though is how the Italics play into this: I assume they're not uniwidth with the Romans, but are they uniwidth among themselves?

BTW, here's a nice new uniwidth design that really pushes the weight range envelope:
http://typographica.org/typeface-reviews/axia/

And here's an old related thread:
http://www.typophile.com/node/61252

hhp

@hrant:
In order to not hijack this thread, I will be glad to answer your questions in the Benedictine Pro thread.
Thanks.

I’ve been meaning to develop a list of these.

QUESTION: Is there a term for typefaces that employ this “different weight, same width” technique?

Chris, if you mean "different weight, same width" then that's what I use "uniwidth" for. Some people call it "duplexing" (from way back actually) but there's a confusing Two in that term, plus no reference to width.

BTW it doesn't have to be just weight: like in Sabon and Asap it could include Italics. Or even multiple styles, like in my Daam Entity from the 90s:
http://themicrofoundry.com/s_latin.html

hhp