Ah, yes. The “But WAIT!” moment is always the best part.
I always loved the infomercials for the hair-straightener that was like a rotating heated (I think) brush. I like all the girls with one half of their hair super-frizzy and puffy and the other half glossy and straight.
I love the crafty things where you make stuff out of plastic loops and yarn and popsicle sticks. You picture this person’s house where every room is crammed with little dogs, flowers, fire trucks, trees, Statues of Liberty all made on their Magic Loopy Loom Crafter Gizmo.
And of course, that’s what all their friends get for Christmas and birthdays, too.
Not really infomercials per say although much longer than a 30 sec ad, the old Ronco spots like:
The Pocket Fisherman
The button stapler thing
The Glass-Cutter thingy you used to cut the tops off bottles to make drinking glasses
Mr Microphone
“hey good lookin I’ll be back to pick you up later!”
I hate anything with Billy Mays in it, I HATE his fucking voice. Not to speak ill of the dead, but damn I am glad he is not around to make any more commercials.
the shake weight is fricking hilarious. My fave, hands down.
My favorite informercial of all time was the one with the little latex thing you put in your bra to make your titties bigger. 30 minutes of girls fondling each other and close-ups of cleavage.
My grandparents had one of those things in the 60s, and actually made quite a few drinking glasses and ashtrays (Grandpa was a heavy smoker). They had to sand the edges down carefully, but they got quite a lot of decent glassware from the thing. Grandpa was a metal shopper anyway, so he had access to the abrasives needed, and he’d just grind down the edges when he was working on other stuff.
Nowadays, of course, only booze comes in glass bottles, pop comes in plastic.
We had that also - and made neat stuff, though the kit we had gave us some sort of alcohol burner or something th heat the cut edges with to help smooth them.
Remember the ‘stained glass’ kits that gave you some sort of black goo in a squeezy thingy to make the outlines and then you used colored goo in squeezy things to color in the cells?
Ha! found it online gallery glass!
I love the commerical for Sears Opitical where the half blind lady calls in her cat for the night and it’s actually a raccoon.
I also like the Safe Auto “Justin Case” commercials. 'Cause every job I ever had there is always some smart aleck kid that thinks working at a job like that is a GREAT THING and really tries hard to make it in a job with no future. 
I loved the series of commercials in the 80s for Grandma’s Cookies. In each one you had the Grandma and her old lady friends and Grandma was claiming she made the cookies herself and with each commerical her old lady friends were getting closer and closer to the truth, that Grandma was BUYING her cookies not making them
To this day, I still want one but have never seen one.
My favorites on these are the befores:
is shaving a chore? (woman with a rusty razor)
are pancakes a bother? (woman pouring batter directly on stove)
When I was in high school/college it was all about Susan Powter’s Stop the Insanity.