Ubuntu – the default vim colorscheme

GNOME Terminal supports 256 colors, but doesn't advertise its support. You can override vim's autodetection by putting the following:

if $COLORTERM == 'gnome-terminal'
  set t_Co=256
endif

in your ~/.vimrc.

Note: if you use GNU screen, it will happily eat those 256-color codes and convert them to basic 16 colors. A better fix is to change TERM to xterm-256color before launching screen/vim.

Update for 2017: if you have a sufficiently recent Vim (7.4.1799 or newer), and a sufficiently advanced terminal emulator (xterm, or gnome-terminal based on a sufficiently recent version of VTE), you can :set termguicolors and terminal vim will use full 24-bit colors as defined by your vim theme using highlight guifg=#rrggbb guibg=#rrggbb.

Generally you can use the "build-dep" command of "apt-get" to fetch dependencies to a package. Use it like this:

sudo apt-get build-dep [package name]

Or more specifically for gvim:

sudo apt-get build-dep vim-gnome

After that you should be able to compile gvim/vim either without further intervention or with only small set of dependencies to resolve required by a newer version of gvim/vim that you are compiling.

As Marius noted one such dependency resolution is installing libssl-dev manually:

sudo apt-get install libssl-dev

Enjoy!