I run a desktop and a laptop and am using both for a large project that I’m creating in Scrivener. I’d like to be able quickly and straightforwardly to synchronize the project across the two computers. I’ve tried Dropbox as a means of doing this, but it doesn’t work as smoothly as I’d hoped. I had a look at ChronoSync, but it just seemed too complicated - I’m amazingly tech-unsavvy, so I need an unchallenging solution. What clearly doesn’t work is using a memory stick to transport the files between the two computers; when I do this, the project on whichever the target computer goes completely haywire.
This or a variation of this would probably be the best option. Carrying the SCR file on a thumb drive or copying it from one drive to another would be the way to go. I do not understand how this would go haywire for you? I use the sneaker network method between two satellite computers and a network solution on two computers at home. Since SCR files are actually packages if you do not zip them prior to “syncing” you may run into a few snags or even file corruption (See this thread Working off of network drives (MobileMe, thumb drives...) )
Can you go into a little more detail why the USB thumb drive method is not working? Maybe we can address that and get things going smoothly without getting to technical.
Make absolutely certain that all of your projects are closed before copying or moving them around (this includes sync services like DropBox and ChronoSync). If you drag an open project to a thumbdrive, then drag that project to another computer and attempt to open it, you increase the chances of projects going haywire, as you put it. Best practice is to just shut down Scrivener before transferring your information to the next computer.
If you have been doing that, then you might simply be having problems with the thumbdrive. Old drives in particular can corrupt data. Buying a new one (they are cheap these days) might solve your problem.
I also do the laptop to desktop back and forth, and I have found that DropCopy at http://10base-t.com/macintosh-software/dropcopy/ has worked best for me.
It installs easily and all I do is make sure that it is always turned on on both machines. Then, if I am sitting on the couch and have finished writing for that session, I simply close Scrivener, and then drag the .scriv file onto the DropCopy circle and it shoots over to the desktop of my iMac. I can even hear the chime from the other room to know that it made it. Then the next time I sit down at the desktop, I just drag the file into it’s proper place.
What sold me on this particular method was that I kept getting lazy and forgetting to take a copy from laptop to desktop via USB stick, and now that I’ve reached the end of my novel and have started revision, I have become even more paranoid when I don’t have a current backup. Also, since DropCopy works over your home network, it doesn’t cost bandwidth to send to an outside server and then download back to the other computer, which is great because my provider has stiff limits on bandwidth.
Glad to hear that method is working for you, BUT
I still think it’s safer to ZIP the .scriv file first, before sending it to the other computer.
What if you had a power failure, just as you were trying to send an unzipped file?
Remember, it’s a package containing zillions of files.
Always best to ZIP first, in my opinion.
Amber, I have mastered saving my projects to DropBox, for which I am inordinately proud of myself (I only used one computer, so I’m not dealing with the same problems as the OP). But I’m curious–I use the “backup to” function in Scrivener, and back the projects up as .zip files. If I were to close the projects first, how would I use that function to back them up?
I apologize in advance if this is a really stupid question, as many of my technical related queries are. 
The backup feature makes a copy and would not be effected by SCR running (Since the backup would not be open in SCR at the time)
So if you copy the ZIP file no worries BUT like Amber suggested if you ever want to copy the actual SCR project you are working on (Not zipped) then close SCR before copying.
If that makes any sense?
Yes. 
The Backup To feature essentially replicates the steps of closing the project, finding it in Finder, duplicating it, compressing it, and moving it to a new spot. If you are already working Scrivener, that’s by far the easiest way to create a backup. My advice for closing the project was strictly for people who are taking these manual steps on their own (or with the help of some kind of tool, like Chronosync), but have neglected to close the project first. This will make a mess of one’s backups.
I use Windows Live Sync to keep my laptop and desktop synchronized. I sync my documents folder so everything I do in any program is seamlessly synched (sp?).
It works so well that I am spoiled, and don’t have to think of emailing files or using a jump drive. As long as both computers have access to the 'net (at some point after changes are made - does not need to be continuous access), changes show up from one machine to the next in seconds. It’s free and relatively easy to set up (for a non-Mac product, I suppose), works in the background and makes things simple.
-Jennifer