I'm using the free version of plot.ly to do plotting from an arduino. Here's a real-time feed, where you can see the effect of last night's irrigation on my soil moisture sensor readings:
https://plot.ly/~WhiteRabbit/997
It's very similar to Xively, but I like how I can easily pan and zoom the data. That's helpful as you get a bigger dataset, like this:
https://plot.ly/~WhiteRabbit/869/
Plot.ly has demo arduino code on their website you can use as a starting point.
Also, I have read how some people are using mysql to collect their data and graph it. I'd like to learn how to do that too, as I think it would be a good data archiving tool, and would provide additional ways to slice and dice the data.
With these solutions, you don't need to be dependent on owning or using a Vera.
I'd be interested to read about what other solutions people are using.