Dare I say it ... Motorway Madness!
Flashed like billy-o, with the JP flashing and the dot matrix square on the top of the trail turned into a giant red arrow pointing at the flashing JP.
BWB's Pyramid-style one was great as it'd suddenly say 'Red Sky at Night, Player's Delight..', the background of the centre board would glow red and it would start belting out '.. its like that, and that's the way it is.. HUH!!' (Run DMC vs. Jason Nevins I fink it was)
Arabian Nights was good when it used to go 'Shazam!' and flash furiously, but they chipped-out the IM, or so I was told?
I guess nowadays you could say the IM on Red's Invincible is a bit obvious - it fills the name, continues flashing and even has an explanation of what happens once you've filled the name. Can't really ask for a simpler game really.
The IM on Hurricane, Wildfire, and clones... lovely massive flashing stuff. And you can't beat lovely massive flashing stuff, can you.

This machine may at times offer a choice where the player has every chance of bankruptcy