Unfortunately, I can't figure out a way of uploading the photos I took of this plant that's been popping up in my pots, so I'll describe it to you the best I'm able. :(

It's a small plant (about an inch at it's highest), with a fleshy red stem. The bottom leaves (and the first leaves to appear) are small and green, wrinkly, and with no markings or patterns. Eventually other leaves begin to grow, which are lighter-green, starry or jagged-edged, and with a bit of a criss-cross pattern on the back of them. These leaves are bigger and wider.

These plants definitely look suspiciously weed-like to me- HOWever, I don't think I've seen them elsewhere, not even in the back of the garden where all of the weeds congregate. :) I'm thinking that it might be a "compost plant", but if it is, I can't place it and it doesn't really appear to be growing up into anything.

It doesn't have a scent but it's roots are sorta sweet-smelling- kind of strong, a little bit like lettuce. So I'm not sure. They aren't hard to pull- the roots go down far but they don't really spread.

Also, if it is a weed, I'd be happy to know what kind ;) (but... if you could include the common name with the latin, that'd be great, because I don't know all of the latin names yet, lol).

Thanks so much!