Anyone using Money Market Funds

I don't but never did.

I'll likely buy some in my RRSP account since it pays ZERO interest and I obviously can't get cash in and out into high interest savings accounts.

Outside the RRSP, never considered, and unless something changes (i.e. they offer better rates than high interest savings accounts), I won't.

I know that Laurentian bank was offering a saving bank account at 3.5%. I don't know if it's still available though..

I use Money Market Funds typically in RRSPs for parking money temporarily. They pay little or nothing now but that's not always the case.