Again, this is stuff that isn't really seen too much on the internet, and even then only in relatively small doses, with certain exceptions, e.g.
http://www.drbilllong.com/index.html(an interesting blog, especially of the spelling persuasion, but has erudite and thoughtful posts),
http://phrontistery.info/(a sesquipedalian sanctuary, many people are familiar with it, but this is the definitive place to investigate or cultivate a word-nerd's appetite, and will often sufficiently sate it, I should go here and filter through and find more words to add to the lists/discover, though, I have gone through most, I may not have written them down),
http://www.wordnik.com/(a user-driven word community/aggregator, which often compiles interesting, if erratic lists, I have yet to decide if I want to submit my content over there, though I should, I think),
http://freerice.com/(a fantastic cause and great time-killer, a word "quiz" which will swiftly expand your vocab with a simple, straightforward interface, if you answer five multiple choice questions in a row, you can nearly feed a person for a day),
http://www.studystack.com/flashcard-434362(a Phrontistery teacher, using the collective words from the Phrontistery and doling out flashcards to drill the words into your head, can be boring, but if you listen to some wordless music, you can compound many words into your head [I recommend you hearken this: http://youtubedoubler.com/video1=AYw7eJYadco&start1=10&video2=HMnrl0tmd3k&start2=0&authorName=rainy+mood]),
http://www.iep.utm.edu/fallacy/(in general, just some edifying stuff sprawled throughout, but the fallacy section bears special merit, as it will promote good grammar, defter and more critical thinking, and new concepts to view),
http://www.talktalk.co.uk/reference/dictionaries/difficultwords/(The Dictionary of Difficult Words, a name which speaks for itself, it is huge, but the layout is not entirely ideal, but I don't think I've fully traversed it, it is, nonetheless, a brilliant resource),
http://users.tinyonline.co.uk/gswithenbank/unuwords.htm( a list of unusual words, interesting if you are looking for grossly impractical words and ones of interest, though, you will look like a jackass if you try and foist them on someone you know, it is not very definitive or comprehensive, but it's a nice, edifying, and quick read), http://www.islandnet.com/~egbird/dict/dict.htm( The Grandiloquent Dictionary, pretty big, not an ideal format, but fun to read, I think I've feathered through most of it, and it is among the better resources for word-related esoterica, all-in-all, an excellent read),
http://www.glyphweb.com/arda/words.html( a relatively[I mean this loosely] mundane assortment of words found in Tolkien's oeuvre, don't be quick to write it off, as it is actually pretty interesting and well-arranged, but you can find these words with a standard word-a-day generator, e.g. Merrian-Webster, Doctor Dictionary, etc.),
http://wordsmith.org/(Speaking of word-a-day, Wordsmith is possibly the best resource to utilize, with many facets to discover and analyze, and is very good to the neglected and jilted words that often fritter away), and finally
http://www.kokogiak.com/logolepsy/(the LL, which I should also re-investigate and add new words to things/learn more, though I believe I've gone through it entirely, the Luciferous Logolepsy is akin to the Phrontistery, but both have especially rare or fascinating words).
