I almost never have more than $100 in cash on me. I keep $4.00 in a compartment in my car for a bridge toll, just in case I somehow forget to have cash. Most of the time I carry an average of about $75. I try to have a few dollars in quarters for parking meters too.
Almost everything else I handle on a debit card. Gasoline, groceries, and other stores are usually debit card purchases. Restaurants, movies, entertainment stuff, etc. are usually cash.
However sometimes I like to use my debit card to pay for the meal at a restaurant and then I'll leave cash for the tip. That way the server can decide how much of my tip he or she will claim for income taxes.
I've eliminated the option to use credit cards for another couple of years or so until I've eliminated all of my consumer debt.