To answer the details of your question: I would go with Dropbox .
UbuntuOne is also good even for non-Ubuntu users, and of course Google drive is the (big) new block player.
They are compared as follows:
Service Free*1 NextLevel*1 NextLevel($)*2 Features Dropbox 2 50 $2.5O One Folder, best gui sync tools. UbuntuOne 5 20 $4.00 Multiple directories anywhere GDrive 5 25 $2.50 It Google. *1 GB *2 Cost per month
To answer the title of your question:
If you want something more suitable for programmers, I would use git:
Install gitx first (linux readers, this gitg) as this is the most popular gui for git:

For the "flow", I can also refer you to my notation of various functions: What are the basic concepts of git, github, fork and branch. How does git compare to SVN?
Using gitx or gitg, a specific thread looks like this:
1) Make some changes to the files.
2) Use the "commit" tab of the tools to find out what has changed ("uninstalled"): 
3) Add the file by dragging it from the "unsteady" to the "delivered":
4) Give a commit message 
5) Commit the file. 
6) Then I click it on the remote in the command line using $ git push remote
or I use gui by right-clicking and choosing the second wizard - see here: 
.
If I am sharing with others, I often need to do git pull
in order to get and merge with other chnages) before you can do git push
The github part does init, push, and clone, but I would say that I just read these tutorials more than the SO question. Basically, I do this:
- Configure repository locally in git:
git init
git add .
git commit "Initial commit"
Configure github:
Create a github repository using github ( https://help.github.com/articles/create-a-repo ) and then click on it a local repository, as in:
git click the initial wizard.
If the repository already exists in github, but not on your local computer, then you click on the remote link, and then on the terminal type git clone
[paste here, for example. ctrl-v]
If you start with github:
- Make changes to the code.
git pull
- get the latest version in your repository and merge any changesgit add .
Add all modified filesgit commit
-m "message"git push
# is the default initial wizard.
If at the end of the day you decide to go with something simple, such as Dropbox, you can use my referral link - http://db.tt/pZrz4t3k - to get a little more than the standard 2 GB. Using this, we get an additional 0.5 GB, however, which of these routes is up to you and your needs. I use all these services (git, github, UbuntuOne, Dropbox and googleDrive, so I do not recommend them over others - it depends on the needs).