@Panic the fonts in your signatures are too in-your-face for the backgrounds that you have. Experiment with different combinations of layer blend modes; look at chrisco97's signature, see how the text "fits" with the rest of the picture? Also (the second signature especially) doesn't have much depth to it--sometimes that's okay--but when there's random lines all over the place generally the image is abstract and it has to have more than three layers of depth. The colour combinations aren't well thought-out, and they look better in black and white. My advice would be to learn about layers because it doesn't look like you're using them effectively. Do a few of the stickied tutorials, you'll improve quickly.
EDIT: since this has basically been a necropost (that image was posted over SIX MONTHS ago) here's a new image. I'm not trying to being disrespectful, but he hasn't logged in since last October and surely there are bounds of reason. Anyway, the stocks are a photo I took of lego peices and a soundwave that I took a screenshot of in foobar2000.
Okay, I was adding a stock of a city a nighttime behind this to fill my whole desktop. I messed around a bit and got this: