For the past couple of weeks, I have been attempting not to store anything on my own hard drive, to try to test out the cloud services of several providers for document storage and collaboration. It has been a mixed bag, to say the least.

Cloud services store files on their servers so you don’t need to worry about backups or available computers. They can be as simple as a file repository to more sophisticate things that create entire networks of virtual computers for applications and databases.

Every cloud provider has lots of fine print that mean you have to kick the tires pretty carefully before you can understand what is offered and what isn’t.

The three providers that I tried were Microsoft’s Live Office, Google Docs, and Box.net. The first two are free. Box has free accounts, but you probably want to make use of one of their paid ones that start at $15 per month. All three have been busy adding features to their services over the past several months, and that is the first thing that you notice about cloud computing: things change, and sometimes on a daily basis. So evaluating these moving targets means a lot more work than just installing some DVD on your PC. You have to periodically return and see what has been added.

Microsoft Live has made the most improvements over the past year, but it still is a hodgepodge of services that have knit together its Hotmail email hosting, Skydrive backup service, and hosted Office Live services. Of the three, they have the best solution if you want to upload PowerPoint slide decks and be able to quickly make adjustments to either the slides themselves or the speaker notes that are shown underneath each slide. Google Docs ignores the notes, which for me is an issue because I use them as prompts for my speeches. Box will let you edit the notes and the slide data, but only after opening your slide deck with Zoho, a hosted open office solution. It isn’t all that much trouble, but certainly not as easy as Microsoft’s Live Office.

Each service has varying limitations on the maximum file size they will allow you to upload and your overall storage allotment. Box has a limit of 2GB per file for its paid accounts and 25 MB for free ones. Skydrive allows up to 50 MB per file. Google 1 GB per file sometimes. I say sometimes because of the way they calculate the overall storage quota. If you convert any MS Office files into their own formats, these files don’t count towards your storage allotment. Microsoft’s Live Office gives you 25 GB of free storage as part of its Skydrive service. Box free accounts give you 5 GB, and the paid accounts can up that to 500 GB or unlimited if you shell out more dough for the enterprise version.

The other part of using cloud services is it makes sharing and collaborating with your documents easier than having to send email attachments around and getting bogged down in resolving different versions. The goal here is to use email for the notification portion, but not for the actual transport of the documents. All three make it easy to send a link to your file to your collaborators. Goggle has made the most improvements here and there are some interesting near-real time editing features that they have added into their Docs platform. The only catch is that all of your collaborators have to have a Google account. Microsoft and Box can send links that anyone can open to view and edit all of the files in a particular folder without requiring them to sign up for their services.

Microsoft and Box both have some interesting tie-ins with social networking apps that can post notifications to Facebook, Twitter and LinkedIn status feeds so your followers and friends can see what files you are working on.

So how successful have I been with sticking in the cloud? Certainly, old habits die hard, and to resist the temptation to save my files locally is tough. I wish we could have one cloud provider that combined the best of the three services.