The shadow
Tz gumball
Sttng Borg battleship
And Xmen for the win ...

I always get a kick out of LAH Crane. Timed skill shot to catch the crane before its destination for extra points, then it physically moves it across the playfield to the lock.

Shadow ball lock (go to 5:25 if the link doesn't start there):

#t=325

I am a HUGE fan of the ball lock for 'Looped In Space' in Big Bang Bar. Pretty much my favorite part of the game.

The Shadow is the coolest. I also like SS and BSD. Both are pretty cool locks.

Verne's World has 3 cool ball locks, but the hot air balloon one is the best of the 3. The magnetic house ball lock on Jolly Park is another really neat one.

Dr Who
STERN INDIANA JONES
SHADOW
TO TAN
CV
ROLLER GAMES
LAH

Roadshow (Funhouse)

Lost In Space

Shadow
then LAH for me.

Love how the skull has 2 chrome eyeballs.

This one is a little out of left field, everyone might not know it, but Bushido has a pretty sweet ball lock. It's a little reminiscent of the Deadworld mod on Judge Dread, but it ejects faster.

TSPP

Agreed ^^^^^

To be fair, Bushido looks to be more like the I500 turbo than JD's deadworld.

Not a huge fan of JD as a pin but I think the Deadworld as designed originally is just amazing. Balls become moons orbiting a counter-rotating Deadworld planet and then a magnet crane grabs them and dumps them on the playfield.

I do agree with the criticism that the unloading can be slow.

I500 is pretty awesome how the balls come zooming out of the turbo. And it is an ingeniously simple design. For those unfamiliar, the balls sit in a round trough with a raised edge that keeps them inside and separated by fan blades. The fan blades are curved from the bottom meaning that as the speed of the fan motor increases the balls climb up the sides of the blades. So in order to release the balls, the game simply speeds up the fan motor, spinning the balls fast enough to raise themselves out of the round trough and come speeding out of the turbo.

I think those two games are my favourites, but partly because I've played them enough to really observe and appreciate the mechanisms involved. Many games have some kind of genius mechanical design to marvel at! And it is especially cool when these are ball locks.

Shadow, FT, IJ, TOTAN...all cool.

I'll add to the Shadow chorus, mostly because it's such a neat effect. In the not-a-DMD category, I love the lock on Radical!, mostly because of the clever logic that prevents two balls from getting in there--if you manage to defeat that logic, free multiball!