glazomania: An unusual fascination with making lists.
glossophobia: An abnormal fear of speaking in public or of trying to speak (often associated with stuttering).
gnashing teeth (excessively): See bruxomania, brycomania
gnosiophobia: An irrational dread of knowledge.
gold: See aurophobia, chrysophobia, ocrephobia
good news: See euphobia
Graiomania, Grecomania: An excessive passion for things Greek.
graphomania: A mania or an excessively morbid impulse and desire to write.

If you would be incisive,
be brief, for it is with words
as with sunbeams.
The more they are condensed,
the deeper they penetrate.
-Robert Southey (slightly modified)
You can suffocate a thought
by expressing it with too many words.
-Frank A. Clark
graphophobia: An aversion to writing or a morbid fear of having to write, especially hand writing.
This may be a result of a fear of criticism of one's handwriting and misspellings; as well as, a fear of committing ideas to paper for others to see.
grinding, or excessive clenching of the teeth: See bruxomania
gringophobia: In Spain or Latin America, an intense dislike of North Americans or white strangers.
gymnogynomania: The obsession of the "peeping Tom"; male voyeurism. A male voyeur is called a gymnogynomaniac.
gymnomania: 1. A compulsion to be naked. 3. An abnormal interest in nakedness.
gymnophobia: An excessive fear of nudity or the sight of a naked person or of an uncovered part of the body.
You can't blame nudists for being
the way they are.
They were born that way!
-Anonymous
gynecomania: Satyriasis, an abnormal, excessive, or insatiable sexual desire in the male for women; also satyromania.
The trouble with some women
is that they get all excited about
nothing—and then marry him.
-Cher
Few people make a deliberate choice between good and evil;
the choice is between what we want to do
and what we ought to do.
-Anonymous
gynephobia, gynophobia: An abnormal fear or hatred of women or any association with them.
A misogynist never talks about women's rights,
but has plenty to say about their wrongs.
-Anonymous
gynonudomania: An overwhelming urge to tear off a woman's clothes.