I like free and I like options.
I already have written about Microsoft’s awesome SkyDrive storage previously here along with other options here.
I really like using DropBox to hold my Titanium Backup files; my Android phone (Rooted Samsung Galaxy SII/Epic 4G Touch) synchronizes my nightly automated Titanium Pro backups to DropBox. This provide me with one more source for me to have access to my phone applications and settings should they get hosed or I need to ‘go back’ to them.
Right now you can get a whopping 50GB Free lifetime storage from Box.net. The forever part is crucial here, since it’s not some gimmick offer that’ll turn into a lemon after a few months of use. The space is yours to keep. Plus the file size limit gets a bump to 100MB, up from 25MB, if you get the app before March 23, 11:59PM. There are no strings attached, either; just download the app and sign in or create a new account FROM YOUR PHONE FIRST to get the free storage, which is then accessible from any device — not just your Android phone. They ran a promotion like this for the iPhone 4S a while back too. I hope you iPhoners got that.
I use many of these cloud services to store data – documents, pictures and encrypted files that I can ‘afford’ to lose. I have loads of photos, technical documents, class/school work and other notes stored. However I don’t store ANY vital information in ANY cloud service; ever. No passwords or keys, no bank account information etc.. I just don’t trust anybody to be safe with my data like I would. But they provide an invaluable service for sharing and collaborating with family, friends and associates.
So take advantage of this while you can and utilize technology to be more productive and have more fun!
[As a footnote. I have the Dropbox, Skydrive and Box.com applications installed on all my machines – BUT they are not set to start at startup and I run/turn them on manually every couple of days. I personally leave VERY few connections to the ‘outside’ world open on any of my systems. Especially ones that I have no direct control over. You may not care, but I’m the ultra paranoid type of guy. You know the type who has worked in the IT security industry for a few decades who might have an idea of what is safe and reasonable. 
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