Would you pay $10 a month + (some budget you determine) to receive a "You're doing X this weekend" type email/calendar invite . It would be complete with instructions of what you need to do, where you need to be and what it is.
I might bend it to be customer pays tho w/ no kickback so that the customer knows we're in their corner. Otherwise I may as well just send everyone to whomever pays me the most.