My first thought was what Sergiy posted, but an alternative is to create a symbolic link in your home directory:
ln -s data /long/path/to/deep/directory/data
Now you can just cd data ( from your home directory, otherwise it's cd ~/data ) when you want to get there. This has the added advantage that if you open nautilus and want to go there graphically you can also just click on the data link in your home directory.