The internet archive has got a huge amount of online texts that caan be downloaded or read online.
It has reciprocal agreements with many international universities and so has some extremely obscure texts, all available without an account.
For some reason the university of Toronto has got a large collection of Royal Navy records (including memoirs and logs)
You can access the internet archive here - and search it by keyword.
I found this rather good collection of eye-witness accounts of The Battle of jutland at the Internet archive - it ranges across comanders to surgeons and gunners - a great read.
As an interesting aside - the Internet archive also has a section called the wayback machine - which has taken regular archives of the internet almost since its inception. It is a brilliant way to view a website that has disappeared from the web, or that has been re-built and lost some content.
You just enter the old url and it presents you with a list of dates to view that website at.