Keys and emotions

------------------------------ Major Keys ------------------------------

C Major: Very emotional. Tender, emotionally vulnerable, childlike, nostalgic in an almost sad way
G Major: Similar to C major, although to a lesser degree
D Major: Bright, joyful, triumphant, energetic. Similar to C or G major emotionally, but in a much brighter and happier way
A Major: Don't really have a strong feeling with this one; I haven't heard this key often enough.
E Major: Otherworldly, surreal, like floating on a cloud
B Major/Cb Major: Sounds like a slightly more "serious" version of C major
F# Major/Gb Major: Don't really have one
C# Major/Db Major: Similar to D major, but sounds almost sad, like it's hiding a tinge of regret behind a half-hearted smile
Ab Major: Don't really have one
Eb Major: Down-to-earth and serious; mechanical, although not to the same extent as Bb Major
Bb Major: Stoic, mechanical, strict, rigid; military-like, can be triumphant in certain circumstances, although not in a very emotional way
F Major: "Neutral" is the first word that comes to mind

------------------------------ Minor keys ------------------------------

Minor is quite a bit more complex, since the harmonic minor scale used in tonal music (raised 7th scale degree) changes the mood quite a bit. In general, I don't really associate specific minor keys with specific emotions; rather, I tend to associate "minor" itself with a specific emotion (either fear/evil or melodramatic sadness depending on the context), and the specific key kind of colors it subtlely by sounding like a "corruption" of the parallel major (if harmonic minor is used - if it only uses natural minor, we don't refer to it as being in "minor", but rather in the "Aeolian Mode", which is beyond the scope of this discussion). This is why I rarely write in minor; I find that (at least with harmonic minor) it has much less capacity for emotional expressiveness because it can't help sounding dark and moody no matter what the context. I can give a few specific feelings that come to mind with specific keys off the top of my head, although its far from a comprehensive list:

C Minor: Since I already associate C major with a kind of nostalgic sadness, this just sounds like an almost comically melodramatic version of C major in most contexts.
D Minor: An "evil" version of D major. Instead of being the victory song of the good guys, this is the victory song of pure evil winning out over good. (Think Final Bowser from Super Mario 64, which is in D minor.)
A Minor: Gloomy, melodramatic - since A major doesn't really do anything for me, this is basically just a really "generic" minor sound to me
E Minor: Creeping, unstable; phrases sound "wrong" and almost unfinished in a way, like things are still left unsaid or unresolved even when the "story" is over
C# Minor: Stormy, dark (think Moonlight Sonata)
Bb Minor: Intense; like Bb Major, except with a significant tinge of urgency
F Minor: Creepy, unsettling; like E minor, but with less of an "unfinished" feeling