Earlier this week I had coffee with Ben Fulcher who told me about his online collection comprising about 30,000 time series, mostly medical series such as ECG measurements, meteorological series, birdsong, etc. There are some finance series, but not many other data from a business or economic context, although he does include my Time Series Data Library. In addition, he provides Matlab code to compute a large number of characteristics. Anyone wanting to test time series algorithms on a large collection of data should take a look.
Unfortunately there is no R code, and no R interface for downloading the data.