That first video is of a demo you can download from here: http://developer.download.nvidia.com/SDK/10.5/direct3d/samples.html#rain. I don't think it's right saying it's DX rain, the demo was made using DX but this can be done in OpenGL as well it just so happens to have been done with DX.
Nice example of DX rain
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That first video is of a demo you can download from here: http://developer.download.nvidia.com/SDK/10.5/direct3d/samples.html#rain. I don't think it's right saying it's DX rain, the demo was made using DX but this can be done in OpenGL as well it just so happens to have been done with DX.