Nifty trick with bundler and rvm. In your app directory:

gistfile1.txt

$ echo "export PATH=.bundle/bin:$PATH" >> .rvmrc
$ bundle install --binstubs=.bundle/bin
$ cd ..
$ cd <app-dir>

installs binstubs into app_dir/bin, and rvm adds ./bin to your path automatically (and takes it away again when you cd out of the app dir)
no more bundle exec

Once you've done this once, by the way, bundler writes a config file in the .bundle directory, so future bundle install calls will automatically put the binstubs in the same location.