Does anyone know what the maximum number of ad text one can add to an adgroup? I've heard it's 50 but....
Welcome to WebmasterWorld SteveMeme.
I am actually not aware of a technical limit to the number of creatives within an Ad Group, and I'll leave it to others to describe how they use multiple ads - and how many seems like too many.
Essentially, I'd advise you to know why you want use multiple ads in an Ad Group, and then use an easy to manage number of ads as you pursue that purpose.
Below is the guessing part of my response. Pardon me if I am mistaken. ;)
I have a notion that you may want to have many ads about different things within one Ad Group - and then use a wide ranging list of keywords to make them appear. If so, I'd strongly advise against it - as it is probably the least effective way to use AdWords.
Instead, it is much better to create extremely targeted Ad Groups in which the ad(s) are about one thing - and caused to appear by a tightly targeted list of very specific (as opposed to general) keywords about that exact same thing,
AWA