Dropbox has a 'Selective Sync' feature of the 'Dropbox Desktop Application' which allows you to exclude folders that you don't want to sync on a per-computer basis. Using Selective Sync, you can select only the folders that you want to be synced to your computer. It gives you the control to ensure that you have only the files you need on any computer. To save the space on your computer with selective sync, you have to enable the 'Selective Sync' feature. To enable 'Selective Sync' feature, download and install 'Dropbox Desktop Application' on your computer. Click 'Dropbox' icon located at the system tray and click 'Gear' icon. Select 'Preferences...' from the menu. Click 'Account' tab and then click 'Selective Sync' button. You will see the folders in your Dropbox folder. Check mark the folders that you want to sync to your computer. Once selection is done, select 'Ok' button. This is how you can save space on your computer with 'Selective Sync'.