I have to vote for By Dawn's Early Light. There's something majestic about it -- Rumford's been trapped in front of his entire young company but takes it like a man and, with Columbo's gracious blessing, fulfills his final duty as an officer and (for the most part) a gentleman. Great, great dramatic moment.

I like that ride off into the night with the incomparable Gil Melle Columbo theme song at the end of \"Blueprint for Murder\". Let us not forget that this could have been the Columbo walk off into eternity. Very thankfully it wasn't.

I agree about "By Dawn's Early Light". Besides what you already mentioned, Martin, I love the fact that the ambient noise proceeds even after the final frame is frozen in place and the credits begin to appear. It lends an eerie quality, as well as representing the fact that routine will go forward at the academy even in Rumford's absence.
Another final frame that always seems quite eerie to me is in "Old Fashioned Murder". As Phyllis and Janie look on passively at Ruth being led away, without ever outwardly expressing the shock and sadness one would think they'd have for a close family member being arrested, Columbo himself fulfills the symbolic gesture of respect Ruth has always wanted, having an arm to support her. I like how the frame freezes at the very moment Columbo opens the door for Ruth; it gives the impression that so many other episodes did, as well, that there may have been more interaction between Columbo and the murderer than the episode was able to show(of course, probably mainly for artistic reasons, rather than for any limiting time constraints).

The murders in "Deed" and "Framing" were both very arrogant. I was very happy to see them caught. "You just lost your badge, my friend," the commissioner said. Then a second later his life is over. Great writing.

I liked the ending in "College" too but just wish that the final scene had Justin's father in it. I would have loved to see his reaction.

I would have to say Friend In Deed...because it really did surprise me....Jessup:"hey....I don't even live here" Halperin "What???"
...."these are my shirts, my underwear" etc...

very cool ending....but there are many
As for troubled waters...I love the episode but do not like spotting the feather thing at the beginning....too coincidental for me...but the prints on the inside of glove was a good one

Great point about the feather. I feel the same way about Columbo hearing the 'bird' sound of a clock at the travel office in the episode about the murder of the football team owner. It was very coincidental also.

Another very good one is the end of DEAD WEIGHT, with the conversation between him and Suzanne Pleshette that winds down slowly. Is it the only episode that ends that particular way?

Although I don't remember for certain, it seems like "Double Shock" ends in a similar way as "Dead Weight", with Columbo walking away with Mrs. Peck, though perhaps not trailing off in conversation as in the "Dead Weight" ending. Of course, "Dead Weight" has a memorable beginning, as well, if only for the fact that (I believe) it's the sole '70s episode where the credits appear in the opening.
Also, your mention of "Dead Weight" somehow reminded me of how playful the ending of "The Greenhouse Jungle" is, and while it may not be one of the most remarkable conclusions overall, I feel it has one of the best closing lines with Columbo saying, "My wife would kill me", referring to if he had forgotten the African violet. I like how it alludes to the whole business of Kathy Goodland having been made out to be a vindictive, even murderous wife throughout the course of the episode.

Upon reviewing "Double Shock's" ending again, I realized that it's really not very similar to "Dead Weight's" ending at all; somehow I had thought there was a conversation between Columbo and Mrs. Peck in a similar vein as his talk with Helen Stewart.
In regards to "Dead Weight", one aspect of the ending that really stands out to me is Hollister very sincerely telling Helen that he's sorry. One expects the murderer to be apologetic towards someone directly hurt by the crime that was committed ("Etude", "Death Lends A Hand"), but not toward a dispassionate witness to the crime, although, obviously, Helen became more than that.
Indeed, Hollister shows greater remorse toward having hurt Helen than Harold Van Wyck does toward his devoted wife of (presumably) several or more years in "Playback" (an episode with, I feel, an outstanding ending, as well).

re..dead weight...one of my LEAST fave episodes
an interesting story from Suzanne Pleshette

http://www.youtube.com/watch?v=k9qjn18ohR0

"The conspirators".

We discover where they hide the pistols at the end and the solution is nothing less than surprising !