I have a funny story about Dropbox which happened two weeks ago. I have a friend who has been running a travel business for about 6 years. During that time, I've hosted her website, email, etc...for $5/month. I've also spent quite a bit of time upgrading her website with each release of the CMS, customizing things and doubling her disk space 3 times (for free) as her email ate up disk space.
Needless to say, I was losing on this deal. So, one day she emails me and asks how much a server would cost. In an effort to save her money, I ask her why she needs a dedicated server. Her response was, "To share files with a new part-time helper." OK, so you sure don't need a dedicated server for that and I recommended that she try Dropbox and if she doesn't like it, let me know and I'll spec out a server for her if that is what she really wants.
A week later she asks me to give her the login details for her account so she can move her email and files over to a new server. Surprised, I ask her what provider and how much she's paying. She signed a 13 month contract with a no-name, 1 person company for $750/month. Oh, and he's not hosting the website...just files and email, so I get to keep managing that.
Lessons learned:
1) I'm apparently charging WAY too little for services rendered.
2) Don't break your neck helping people for nothing, expecting some kind of return later.
3) Don't recommend Dropbox (j/k)