The source code is available on the ASCII Invaders homepage.
ASCII Invaders binary (tar/gz)
(MD5SUM of the tarball: ce91a3f0d33b40822b0f9f975542812c)
(MD5SUM of the binary: 997dd5378c601c46018aa47f5caa255c)
This program is tiny so I didn't make an IPK out of it - just extract the binary and run it from a terminal/console.
Enjoy! (Though you have Mr. Munro to thank - I just typed 'make').