I corks I chose where a mix of pretty and sentimental. One of the corks was even from the champagne bottle we drank the night we got engaged...way better than having it sit in a jar on my counter.
The original tutorial called for drill, but A) I don't have one and B) that seemed intense. I used a corkscrew to start the circular hole and then a sharp knife to carve out a spot for the magnet. I could have just glued the magnet on the back and called it a day, but making it flush gave it a nicer look on the fridge.
I think the engagement champagne cork looks great between my instagram magnets and the Halloween magnets from my aunt. This might be the craft that gave me the most bang for my buck...simple, quick, and pretty. What more could you want?