This is my current Mac OS X bash profile. It formats the prompt nicely, makes it easy to read and throws in some handy features and a few nice aliases for Homebrew commands.

Bashful

# ~/.bash_profile

# Git branch in prompt. From https://github.com/jimeh/git-aware-prompt/

export GITAWAREPROMPT=~/.bash/git-aware-prompt
source $GITAWAREPROMPT/main.sh

# Nicely formats prompt. Current directory path, current git branch then "$" on a fresh line
# $git_dirty verifies if changes are commited or not

export PS1="\n\$PWD \[$txtcyn\]\$git_branch\[$txtred\]\$git_dirty\[$txtrst\]\n\n\[$bldgrn\]$ \[$txtwht\]"

# Ensure Ruby 2.0.0 is used as "system ruby"

export PATH="/usr/local/var/rbenv/versions/2.0.0-p0/bin:$PATH"

# Start rbenv at prompt startup

eval "$(rbenv init -)"
export RBENV_ROOT=/usr/local/var/rbenv
	if which rbenv > /dev/null; then eval "$(rbenv init -)"; fi
	
# Some aliases for Homebrew

alias bup='brew update && brew upgrade'
alias bout='brew outdated'
alias bin='brew install'
alias brm='brew uninstall'
alias bls='brew list'
alias bsr='brew search'
alias binf='brew info'
alias bdr='brew doctor'