BNC database and word frequency lists (Kilgarriff)
Word Frequencies in Written and Spoken English: based on the British National Corpus (Lancaster)
OGDEN's BASIC ENGLISH
Mike Scott's Guardian word list
Moby word lists
Kevin's Word Lists Page
ESL : Vocabulary : Lists
ICAME word lists
Phrases in English
Word frequency lists and dictionary
from the Corpus of Contemporary American English (Mark Davies)
Wiktionary:Frequency lists
Wikipedia:Word lists by frequency
Big English Word Lists
Word lists from Leeds (English, Russian, Arabic, Chinese, French, German, Greek, Italian, Portugese, Spanish)
From Lexiteria (commercial)
SUBTLEX-NL is a database of Dutch word frequencies based on 44 million words from film and television subtitles
Knut Hofland
Computational Language Unit (CLU)
Uni Computing
Uni Research AS