Haven't got a valentine for your sweetie yet? Don't worry, Kate Spade, Your Heart Out, and Orange Beautiful are here! Kate Spade has the best e-cards I've ever seen, designed by some great designers such as Lena Corwin, which is where I found out about them.
Your Heart Out has some cute lil' printable versions.
Orange Beautiful designed a downloadable clever love dice, you can find at Daily Candy Kids.