Many people can’t afford Lane’s massive Arabic-English lexicon, which is considered the most comprehensive Arabic-English dictionary available. Although Lane died before completing the book and therefore the sections completed by his nephew are not on par with the rest of the book, the Lexicon is considered a must for all serious translators of Arabic texts.
Given the size of the lexicon (8 volumes in one edition and two massive volumes in the other), it is also hard to access at times. Having an online version of the dictionary, therefore, is very useful.
Below are links to pdf and dvlu files of the book as well as a site that allows for easy browsing of the book online.