ThinkDesign has a great Halftone Dot Vector Pack available for download. The set includes 28 total, with both clean and grunge versions.
Pictonic Cube is a free icon font set that includes the most useful UI elements for your user interface design projects. As a font, it’s very flexible. For example, you can manipulate the icons with CSS properties (e.g. color, size, shadow, etc.). The font files include EOT, SVG, SVGZ, TTF and WOFF. If you want to edit the icons, SVG files (editable in Adobe Illustrator) are also provided for all icons.
Media Militia is offering a pack of 20 different paint tossing images, some with a white background and some with a black. If you do not like the paint colors, just open the document in of Photoshop, add a new layer and fill it with the color you want. Then change the layer blending mode to Color.