The bottles standing in the window caught my eye, as well as the promotion of only 18 euros for a bottle of obscure champagne. My attention was then drawn to the chairs and tables on the pavement outside the shop, which were playing hosts to a grown-up French family, who, even at 4pm in the afternoon, were a little worse for wear.
I decided this was my kind of shop so I pushed the door open and went inside. I was greeted by the boss, who was very helpful and knowledgeable and I've walked away with a particularly wonderful bottle of Calvados.
They have a good selection of wines from all over France at prices gravitating around 10 euros a bottle. It seems they also do tastings there because they had a special room towards the back where there was a large communal table which looked perfect set up for a tasting.
They also serve food - great platters of cheese and charcuterie for just 6 euros 50, as well as the chef's dishes of the day - and you can go there to buy a bottle, or even just a glass of something, to drink on the premises too. (There were some small tables and chairs in the front of the shop, as well as those on the pavement.)
Well worth remembering if you're ever in the area.
More about this place: http://www.yelp.fr/biz/le-rouge-et-le-verre-paris-2 and http://www.paris-bistro.com/choisir/paris9/rouge_verre_paris_9.html