quoting Rhetorica, Kelatetía:

Luciferous Logolepsy
"[A] collection of over 9,000 obscure English words."
Very much in the same vein as Phrontistery, this also emphasizes obscuranda.

Sadly, the domain expired. A charitable soul, though, has recollected many words from the site here.

But I came here to post a link to a beautiful Etruscan lexicon. Also, this little resource on the Etruscan language.

And the Minoan Language Blog, to round up this Tyrsenian vibe.