Driving to Portland from the south
Known to everyone but me, until a month ago: you can avoid the 50¢ toll when you get off of I-95 (northbound) onto I-295 by taking exit 45 (Maine Mall/Payne Rd) instead of exit 44 (I-295). There is then an exit-thingy off of Payne Rd onto I-295, toll free (its number is 1-800-Portland!!)