Based on Lucky Mike's answer for the stack overflow topic: Navigating through a huge project with vim and unite.vim plugin, this plugin creates a file list and use its content as source for Unite.vim.
This plugin has two methods to generate the file list: git ls-files and find. If this plugin
detects that the current working directory
is (or is inside a) git repository, the file list will be built using git ls-files and the
process will in which case not only be very fast, but will also exclude all gitignored'ed files.
On the other hand, if the current working directory is not a git repository, this plugin will use a
combination of find and grep to gnerate the file list while still exclude all wildignore'ed files.