My sister loves trying restaurants equally as much as I do, so whether I visit her, she comes home or we go on vacation together, dining out is going to be the main agenda. The meal we shared at Derek’s (4411 Main St) was in celebration of our birthdays which come a month apart. It was also a chance to try out Restaurant.com. With Restaurant.com you can purchase a $25 gift certificate online cheaply, between $2 -$5, then you check the list of participating restaurants; which doesn’t include every new Center City hotspot, but it’s a pretty extensive listing. And then print the gift certificate for the chosen establishment. Here’s…