You mean other than Shatner himself, right?
Ha ha, 
On one of those old “comedians sitting around a table talking” shows, Kevin Pollock did a really amazing Harry Caray impression. In both modes: early in the game sober Harry and late in the game slurring Harry. The transition from one to the other was stunning.
One could learn a lot from Pollock. I’ve always found watching someone else do an impression the best way to figure out how do it. But most impressionists do the usual group so for the purposes of this thread this isn’t all that helpful.
Pollak does a “game” where you do an impression with a single word. I can do a one- word Ronald Reagan with the word, “Well…”
Oddball? How about Oddball himself, aka Donald Sutherland in Kelley’s Heroes?
“Always with the negative waves, Moriarity!”
and
Woof woof!
-That’s my other dog impersonation
I do these pretty well if I may say so.
I might be misremembering, but I thought it was one word, and not a word associated with the person.
The rules are loose at best. The “single” word for Jason Statham is “KnowhatImean?”
Fair enough.
“America’s Funniest People” once had a guy parodying a used car salesman. One vehicle came with a laser ray gun (“pew pew pew”), a phaser ray gun (different “pew pew pew”), and a Ronald ray gun (“well”). I’ve never been able to find a clip of that online.
“Megladawwn”
Was “holy cow!” part of it?
I was pointing out there were William Shatner impersonations before there was a Kevin Pollak.
I used to be able to do a pretty good Bill Murray as Carl Spackler but I think my voice is too deep now.
“So…you’ve got that going for you”
That voice and character is the same Murray and (I think Steve Martin) did for a fluff fill in piece on SNL. Basically just saying over and over again
“What the hell is that”
I found it
I can manage Yogi Bear and Boo Boo, Bullwinkle Moose, and Charlie the Tuna, from those old Star-Kist canned tuna ads.
Peter Lorre is easy. On a good day, I can get close to Dan Aykroyd, but not quite all the way there.
My best, and most fun, and most oddball, is the monster truck commercial announcer: “Sunday, Sunday, Sunday, it’s Monster Truck Madness!”
I can do a very passable Edie McClurg.
I’d be very impressed if it’s something like Lucille Tarlek from WKRP or Mrs. Marv from the morning Letterman show. OTOH, if it’s from Ferris Bueller or Planes, Trains and Automoniles …