Today's field trip isn't work-safe, so a head's up to everyone with kids hanging over your shoulders, or a boss who could come strolling past.

I saw a mention of the artist Juan Francisco Casas on another blog, and was absolutely amazed to find the guy does a lot of work using only a Bic pen. Yup, you saw that right--a Bic pen. Below is a link to his gallery, but there are some nudes in there, so be warned.