Does a reader exist

[Houndx]

that syncs the last page read between the iphone and the desktop that also allows me to import my own content for reading? As far as I am aware the kindle app does this, and possibly the b&n ereader app(?), except for the content not from their stores part.

While I don't want to be tied to one bookstore, I don't mind being tied to one reader - assuming that it has all the basic features that I need. I don't mind dealing with converting my books to another format for this.

Since I'm assuming that I want something that does not exist, I may as well ask about another feature that I'm sure doesn't exist. Does a reader exist for both the desktop and the iphone that has plugin support? Because what would be REALLY awesome is if both versions would automatically upload my current position to a website, preferably of my choice, then download it the same way - and I wouldn't mind writing the plugin.

When I say desktop, I mean that I prefer Windows but that I'd be willing to consider OSX, Linux or something else if it were necessary.