Mobility.

For those of you not in Second Life or on Twitter, you may not have known that I was in Philly all last week for the holiday break. I did have my laptop and wireless router with me, but I used that as a "backup". Interestingly, this was a test of my reliance of cloudware apps in lieu of downloaded software.
90% of my time online, I am logged into iGoogle (which includes my GMail, Google Reader, Remember the Milk, and Jott plugins among others), Twitter, and Pidgin (for IM). When I'm away from my laptop, I can easily replace Pidgin with Meebo for all my instant messaging needs.
Work-wise, the only things I'd really be without would be audio and image-editing apps. I have lived without Microsoft Office for over 6 years now, when I made the switch to Open Office. while I'm away, I go one step further and rely solely on Google Docs, which limits me only in page formatting options.
I'm trying to learn from people like Dave Warlick and Steve Dembo about mobility, so lets hear in the comments: "What other cloudware apps do you rely on?"

p.s. This is the start of a small personal project so I can avoid lugging my personal laptop with me to Disney in March. I'd rather not bring it if I have the choice, but ignoring email, RSS, and more for that week would just drain me, I think.