.:Tentacles:.
1. Create a new canvas, any size you want, im using 300*300, and select a transparent background.
2. Fill the first layer with black, and make a new layer.
3. On the second layer, select the rectangular marquee tool and make a rectangle:

4. Fill it with white, but dont deselect it.
5. Go up to Filter » Blur » Gaussion Blur for about 5 pixels.
6. Now go up to Edit » Transform » Perspective and zoom in a little to the top of you rectangle and you will see 3 boxes at the top of it, hover your mouse over the far right one until it turns into a grey arrow, then hold shift and then drag it inwards to make a point:

*now you can deselect.
7. Now still on the second layer go up to Filter » Distort » Shear and do something like this:

8. Once thats done you will see your tenticle:

9. Now just do what you want with it, i made this, with some clouds, and some drop shadow, bevel and emboss, contour, and stroke on the tenticles: