If find an arcade cabinet of Pengo (which is going to be kind of tough these days), you might be tempted to play it. And once you do, you're going to notice that in the middle of the playfield are these blocks with diamonds on them
They've got a couple of interesting features: they're indestructible and if you line up all three of them so that they're touching...
The screen freaks out and you get 10,000 points! As an added bonus, all the Sno-Bees in the level are stunned, for a few seconds
Giving you a pretty sweet advantage (even if it is temporary).
The only problem is that in some levels the blocks are placed in such a way that it's virtually impossible to get them lined up, so if that happens, I wouldn't worry about it too much.