Exactly where does my 126 chassis need regular lubrication?

[goldstone]

I started changing my 420SEL's oil on my own about a year ago. When I used to take the car into a shop for normal oil changes, the tech would also "lube" under the vehicle where appropriate, and that's my question:

Exactly what points should I periodically be re-lubricating under my 1989 420SEL? And also, does it matter what type of grease I purchase and apply?

I really enjoy performing the car's basic maintainance on my own; but naturally, I don't want to neglect anything out of ignorance.

Thanks for any help you can provide!