I read The Happiness Project by Gretchen Rubin (Harper, 2009) during my blog break and immediately set about starting my own Happiness Project.  (Me and everyone else who reads the book, I imagine.)  I'll spare you the details, although it does involve more blogging--which brings me to this post.

At one point during Gretchen's project, she decides to collect bluebirds, because bluebirds are a symbol of happiness.  The connection arises from Maurice Maeterlinck's play The Blue Bird (1908; link is to Project Gutenberg), in which two children--Tytyl and Mytyl--search everywhere for the Blue Bird of Happiness only to find that it was at home all along.

And of course, The Blue Bird is the matinee performed by the students of Madame Fidolia's Academy of Dancing and Stage Training in Noel Streatfeild's Ballet Shoes (1937).  Two scenes from the play are quoted at length in the book; I loved reading these as a child and imagining myself in the roles of Pauline-as-Tytyl and Petrova-as-Mytyl.  I collect books, not bluebirds, but they bring me happiness all the same.

[N.b.  I love the costume notes for The Blue Bird:

TYLTYL wears the dress of Hop o' my Thumb in Perrault's Tales. Scarlet
knickerbockers, pale-blue jacket, white stockings, tan shoes.
MYTYL is dressed like Gretel or Little Red Riding-hood.
LIGHT.--The "moon-coloured" dress in Perrault's _Peau d'âne;_ that is
to say, pale gold shot with silver, shimmering gauzes, forming a sort of
rays, etc. Neo-Grecian or Anglo-Grecian (à la Walter Crane) or even
more or less Empire style: a high waist, bare arms, etc. Head-dress: a sort
of diadem or even a light crown.
THE FAIRY BÉRYLUNE and NEIGHBOUR BERLINGOT.--The traditional dress of the
poor women in fairy-tales. If desired, the transformation of the Fairy into
a princess in Act I may be omitted.
DADDY TYL, MUMMY TYL, GAFFER TYL and GRANNY TYL.--The traditional costume
of the German wood-cutters and peasants in Grimm's Tales.

And many more, all of which I want to make.  Puppet show, anyone?]