I've had the site bookmarked for a long time, but since the last time I looked at it (a year or two ago I think) it's been extended a lot.

In particular, it looks like they've added several of the reference books available from google and archive as web pages, which is handy if you haven't the bandwidth for downloading them (I think I've got about 2Gb of downloaded books - mostly 19thC but some 20thC).

Mick