briantrumpet
Timewaster
When choosing between me and I it is always better to err on the side of sounding stupid rather than pretentious. Obviously just getting it right is another option.
This example is one that's called 'hypercorrection' - people *think* that the correct version is going to sound pretentious (probably because we tend to overuse 'me', and get corrected to 'I' (and sounds grown-up/pretentious to a child), so even when people are grown-up, they think that the one that sounds pretentious (or wrong) must be right. "Me and Mr Penguin are going out to play, Mummy!" "No, that should be 'Mr Penguin and *I* are going out to play', darling!" I mean, how silly does it sound that 'I are going out to play"? OK, let's use the one that sounds wrong then.
The other technique, as I'm sure you know, is just to leave out from the statement the other person involved and see whether 'me' (object') or 'I' (subject) sounds right. There are a few occasions where pretentious grammarians and normal people will disagree whether it should be I or me.