I have mostly had the Greek New Testament and related works in mind as I have been working through Natural Language Processing with Python. One useful resource discussed in the book is a word-list, which are just a simple collection of words gathered from a particular language or corpus. Text auto-completion is an example of the usefulness of such lists. The only ancient Greek wordlist included with NLTK is the Swadesh list, which is fairly limited (only 207 entries).
Before I invest the effort in creating one, does anyone know of any existing unicode Koine Greek word-lists? If not, it should not be too difficult to programmatically compile one from the Greek NT. Either way I will share what I find (and any code which happens to be written for this end).