A slightly more in depth tip today.....
I've seen a couple of different solutions lately for sharing Lightroom catalogs across multiple computers, but in my mind they've all felt a little clunky (like this and this). I don't mean the ability for different users to work on the same catalog at the same time, because this can't be done (as far as I'm aware). When I'm at home I tend to work on my images on my iMac, basically because it's an ideal working environment - I have controlled lighting, a large screen and a lovely big Wacom tablet on which to work. When I'm travelling, I use my Macbook Air to edit. However I'm not a fan of having to create a new Lightroom catalog every time, with all the configuration that goes with it, and sometimes I also like to work on previous images. I want to be able to import new images into my existing main library, which is set up with all my collections, copyright information, keywords etc. So to do this I use Dropbox and it's really quite straight forward. All of the current year's images I keep on an external 2TB USB drive, that's the RAW files and processed TIFFs. This is easy enough to unplug and carry around. The Lightroom catalogs (the .lrcat files) are saved to a folder in my Dropbox account. Once I've done any editing on my iMac and closed Lightroom down, all my changes to the catalog file along with any necessary previews are automatically uploaded to my Dropbox account. This can take anything from a few minutes to an hour or two depending on the scale of the changes that I've made. During this time, all the uploaded changes are also being automatically synced back down to my MacBook, so once it's all finished all I have to do is grab it along with the USB drive and I can edit on my lap. All the paths to the images and plugins (which I also store in a Dropbox folder) are all in the right places so there's no need for messing about with any configuration. It's quite literally plug in and go. And of course it all works the other way round. As soon as my Macbook finds any Wifi, all edits are automatically synced back up to the cloud.

For redundancy, I also use Backblaze to mirror harddrive changes up to their server so that I have additional copies of the catalogs, and I also use a couple of HDD caddies and ChronoSync to make mirrors of the images on the external USB drive, one of which stays in it's dock and the other one is stored off-site. I have been using a Drobo for some time, but I find it painfully slow at times, and less reliable than a simple slaved hard drive.

It's taken me a fair amount of tinkering and experimenting, and I do have a premium account with Dropbox and 100GB of storage which I guess adds an added expense but for the sake of simplicity it works perfectly for me.