Stuff You Need For Tutorial!!!Dots & Holes Patterns -
http://www.megaupload.com/?d=YGSWAW14Layer Effects Scripts -
http://registry.gimp.org/node/186NOTE: If you have any trouble trying to follow my instructions on how to create this text effect feel free to download, and look at the
project file I created so it's easier to understand.

Gimp - 3D Penetration Text
First off go ahead, and add some text to your document.
Right click the text layer, and select "Alpha to Selection".
Then head to Select/Shrink I shrunk mine by 4 pixels, but you can choose how much you want yours shrunk.
Now make sure you copy what's selected on your text right now, then hit delete.

Gimp - 3D Penetration Text
Now paste what you just copied into a new layer.
Right click the pasted layer, and select alpha to selection.
Then make a new layer, name it dots, and then fill it with one of the dot patterns I created, that you can download from the link at the top of this tutorial. (I used the "Dots 15px")
Now change the layer name for the border of your text to "border".

Gimp - 3D Penetration Text
Now the 3 layers we now have for the text we want to give them a bevel, so head to Script-Fu/Layer Effects/Bevel and Emboss... and change it to an inner bevel.

Gimp - 3D Penetration Text
Now your image should look like this.

Gimp - 3D Penetration Text
Now go ahead, and crop the text down, and you we are now done however I want to give this text a little twist, so if you'd like to go along with me feel free if not, drop down, and give me 20 lol Just kidding. Anyway go ahead, and merge the bevels together (just the black, and white layers), for example the border will be merged to it's own layer, the holes to it's own layer, and the inner text part in it's own layer.
Then duplicate the text border bevel you just merged, and then invert the holes so it looks like it has a bunch of dents.
You're final result should now look something like this.

Gimp - 3D Penetration Text