Best Dropbox text editor?

Plain and simple, as the title reads, what is the best Dropbox-based text editor for the desktop?

My requirements are fairly minimal: An unobtrusive UI, offline working capabilities, lightning quick syncing and...that's about it, I guess.

Most of the ones (Ulysses III, Notational Velocity, iA Writer, and so on and so forth) which have all three are Mac-only. Are there any good ones for Windows' desktop?

Also, are there any sites which let me find Windows equivalents for certain Mac apps?