Since Lord Elfboy decided to do ENxP subtypes and Raptor Wizard did ISTP subtypes, I am going to to ISFP subtypes.
Sofia Coppola subtype - Artsy, subdued, works in some kind of sensory aesthetic profession like film, painting, music, fashion, photography or decorating. When you say you're an ISFP, most people agree with you, because you fit their image of what an ISFP should be.
James Dean subtype - sensitive but rebellious, strong and silent and slightly ISTP-ish, but showing a lot more Fi and softness. Quiet but sexy, you can get mistyped as INFP as well ISTP, because really, though you may be cool on the outside, no one really knows a damn thing about you and just keeps guessing. You like it like that.
Couch potato subtype - ISFPs read descriptions of themselves on-line and get offended because it seems like it was based on people like you. You're simple, enjoy watching hours of television, have very little ambition, but are basically a nice and unobtrusive person. You're probably not even interested enough in type theory to be on this forum.
Eminem subtype - people tell you you're not an ISFP because you're too tough or opinionated, but it's clear that when you aren't expressing yourself through performing or writing that you're actually a pretty introverted and sensitive Fi dom. People get way too caught up in the ESTP or ENFP persona you're capable of presenting to the world, and mistake the fierceness of your Fi convictions for you being either an xSTP or an extrovert with "a lot of Te development." You're probably just a counterphobic E6, and while everyone knows you write gangsta rap about locking your girlfriend in the trunk, they seem blissfully unaware of all those sappy songs that make people cry that are based on your daughter, your personal struggles with your drug addiction, and how you guys are beautiful, no matter what any one says, bro.