Sweetest Lock Groove Records

Not all artists press their works with the best sounding lock grooves. Example: Jack White's Lazaretto (Side 1).

However, 2012's Preteen Zenith ‎– Rubble Guts And BB Eye ups the ante with the lock grooves on BOTH sides that are so smooth and melodic (can't tell where it ends or begins) - you can leave them on endlessly for your listening enjoyment.

I always liked Rush's - Fly By Night (Side 1) at the end of By-Tor And The Snow Dog chiming bells.

What other "smooth and melodic" lock grooves do we have out there?
I understand the locked groove and am familiar with the Rush example but for the life on me can't think of one. I don't spin vinyl and longer but that doesn't really matter. Can you give a couple more solid examples?
First let me say fantastic link Abucktwoeighty you are a gentleman and a scholar! Secondly The Kevin Ayers (Soft Machine) solo LP on UK Harvest entitled "whatevershe bringswesing" has a cool lockgroove on side two of gently flowing water.Another type of lock groove is on records stickered with "banded for airplay" every track ends in captured groove,so you must lift the arm and manually advance to listen to each track.I have a Gryphon LP (Red Queen To...?) like this as well as a Grateful Dead (I think Terrapin Station).