Yep, here's one way of doing that:
First of all, download
Play Sound. When an audio file is dragged onto its icon, it will start playing automatically without a user interface, and pressing the escape key will stop it.
To create a keyboard shortcut, download
Quicksilver if you don't already have it. Open it, and press Command-' to open the trigger preferences.
Click on the + icon at the bottom to create a custom HotKey trigger. Type in the name of your sound effect, press tab, and type in 'open with', press tab again and type Play Sound as the target.
Here's an example of how it's set up:
Save it, then double click on 'None' under the Trigger column, and type in the keyboard shortcut you want to use. It should work straight away.