In fact, a good reason for sending out copies to MEPs is that this is leverage on the Commissioners -- the letter is out there and can't be as easily ignored. (Same logic applies to sending to two commissioners).

This is the covering e-mail I sent to French MEPs, roughly translated into English :

I live and vote in South-East England, which you represent for the Green Party in the European Parliament. I'd like to let you know the indignation (or some such word) I feel about the public consultation organised by the European Commission's DG-TREN on the Energy Green Paper.

I'm a member of an international forum for civic debate, The European Tribune, (http://www.eurotrib.com), where, along with political, social, and cultural topics, energy and the environment receive considerable attention. Hoping to make a collective contribution to to the Green Paper Public Consultation, we were astonished by the procedure -- in our view, restrictive and partial -- set up by DG-TREN. In protest, I and a dozen other EU citizens signed (13/09/2006) an open letter to Energy Commissioner Andris Piebalgs, and Communication Commissioner Margot Wallström. A copy of the Open Letter is attached as a pdf file. It explains in more detail our objections to the limits imposed on citizens' expression and what we see as a manipulative way of questioning opinion.

I'd be interested to hear your reactions about this, and would like to ask you, if you share our opinion of the consultation procedure, to make your views known to the two commissioners concerned, and also to other MEPs. At The European Tribune, we think this is a matter of democracy. European citizens should not be kept out, by means of a skewed online poll, of a vital debate to which big private interests have, no doubt, easier and less transparent access.

You could copy in the list of signatories from the bottom of the Open Letter, saying : "Here is the list of signatories" or something less obvious as wished. The list, with a number of different countries lined up, might help to make the reader look twice.

Embed a link to ET where it's mentioned. I don't know if it's worth putting up links to diaries. Don't want it to look too spammy.

I just remembered that Caroline Lucas is on the Industry, Trade, Research, and Energy (ITRE) Committee of the EP. The chair and two of the vice-chairs of this committee have been sent the letter, as have two French Socialist members.

You could include, before the final paragraph, something to this effect:

"Several members of the EP's ITRE Committee, of which you are a member, have been sent a copy of the Open Letter (including the chair and vice-chairs)."