bash: syntax error near unexpected token `('

You should use single quotes ' or double quotes " around the URL in this case (and in general):

wget  'http://www.flareget.com/files/flareget/debs/amd64/flareget_2.3-24_amd64(stable)_deb.tar.gz'

From now, you should use this method in general when you use a string which contain parentheses as argument in a command. That is because parentheses are used for grouping by the shell such that they are not communicated in any way to a command. So, the bash shell will give you a syntax error:

$ echo some (parentheses)
bash: syntax error near unexpected token `('
$ echo 'some (parentheses)'
some (parentheses)

It's because of the brackets. You need to escape them like this:

wget  http://www.flareget.com/files/flareget/debs/amd64/flareget_2.3-24_amd64\(stable\)_deb.tar.gz

Now it should work.

Mine had nothing to do with un-escaped brackets and everything to do with an alias already being defined with the same name as the function.

Alias in one file:

alias foo="echo do something"

Function in another:

foo() {
    # Do something else
}

Both of these files were sourced by my ~/.bashrc, giving me the unhelpful error message:

syntax error near unexpected token (