The fdserv.erl module makes it possible to open
up privileged ports from Erlang running as non-root.

Here is an example from the esmb_browser.erl code:
---------------------------------
...
{ok, Fd} = open_socket(137, []),
....

open_socket(Port,Opts) ->
    case fdsrv:bind_socket(udp, Port) of
	{ok, Fd} ->
	    gen_udp:open(Port, [{fd, Fd}, binary, {broadcast,true} | Opts]);
	Error ->
	    ?elog("Couldn't open socket, port=~p: ~p~n",[Port, Error])
    end. 
--------------------------------

Here we open the NetBIOS-NameService port 137.