I know the holiday period is nearing its end, but I hope this may be of use to somebody planning to enjoy the French Riviera.
All bus journeys served by the Ligne d'Azur in the Nice Cote d'Azur Community of Municipalities - practically the whole department of Alpes-Maritimes - cost 1 euro regardless of the length of the journey. This includes travel to and from Nice, Monaco, Grasse, Cannes, Antibes ... In comparison, train journeys between these towns may cost up to 40 euros per person!
Also, if you travel to Nice International Airport, rather than taking the recommended express buses No. 98 and 99 into town for 4 euros each way, go for a normal Ligne d'Azur all-stops bus. It is a bit slower but it goes almost the same way along The Promenade des Anglais and costs the usual 1 euro.