Java 7, 118 115 bytes

class P{public static void main(String[]a)throws Exception{java.awt.Desktop.getDesktop().browse(new java.net.URI("http://ppcg.lol"));}} Java is not the best language for golfing... Here's the same program in a more readable format:

class P {
    public static void main (String[] a) throws Exception {
        java.awt.Desktop.getDesktop().browse(new java.net.URI("http:ppcg.ga"));
    }
}

Saved 2 bytes by removing // in the URI/L, and another byte by switching to .ga from .lol (indirectly thanks to @Milo)

Java 7, 151 bytes

class P{public static void main(String[]a)throws Exception{java.awt.Desktop.getDesktop().browse(new java.net.URI("http:codegolf.stackexchange.com"));}}

Java is not the best language for golfing... Here's the same program in a more readable format:

class P {
    public static void main (String[] a) throws Exception {
        java.awt.Desktop.getDesktop().browse(new java.net.URI("http:codegolf.stackexchange.com"));
    }
}

Saved 2 bytes by removing // in the URI/L, and another byte by switching to .ga from .lol (indirectly thanks to @Milo)

Java 7, 118 bytes

class P{public static void main(String[]a)throws Exception{java.awt.Desktop.getDesktop().browse(new java.net.URI("http://ppcg.lol"));}} Java is not the best language for golfing... Here's the same program in a more readable format:

class P {
    public static void main (String[] a) throws Exception {
        java.awt.Desktop.getDesktop().browse(new java.net.URI("http://ppcg.lol"));
    }
}

Java 7, 118 115 bytes

class P{public static void main(String[]a)throws Exception{java.awt.Desktop.getDesktop().browse(new java.net.URI("http://ppcg.lol"));}} Java is not the best language for golfing... Here's the same program in a more readable format:

class P {
    public static void main (String[] a) throws Exception {
        java.awt.Desktop.getDesktop().browse(new java.net.URI("http:ppcg.ga"));
    }
}

Saved 2 bytes by removing // in the URI/L, and another byte by switching to .ga from .lol (indirectly thanks to @Milo)

Java 7, 118 bytes

class P{public static void main(String[]a)throws Exception{java.awt.Desktop.getDesktop().browse(new java.net.URI("http://ppcg.lol"));}} Java is not the best language for golfing... Here's the same program in a more readable format:

class P {
    public static void main (String[] a) throws Exception {
        java.awt.Desktop.getDesktop().browse(new java.new.URI("http://ppcg.lol"));
    }
}

Java 7, 118 bytes

class P{public static void main(String[]a)throws Exception{java.awt.Desktop.getDesktop().browse(new java.net.URI("http://ppcg.lol"));}} Java is not the best language for golfing... Here's the same program in a more readable format:

class P {
    public static void main (String[] a) throws Exception {
        java.awt.Desktop.getDesktop().browse(new java.net.URI("http://ppcg.lol"));
    }
}