Although, as Laure pointed out recently, we're a big fan of colour here at ATLA (perhaps it's our sunny climes), if you prefer neutrals, there are subtle ways to bring in colour. Adding colour to your ceiling is one option. It can be high impact in a low commitment way. While the bedroom's the obvious place to try this (We dreamed of painting clouds on our bedroom ceiling, dotted with luminiscent stars that light up when the lights go out.) Here, an otherwise all white kitchen takes on new life with a red ceiling and draws attention to the beams.
Even in a room with a challenging ceiling, this is an easy way to embolden a space, bring it into focus and give it life. Instead of bemoaning your low or oddly shaped ceiling, make it your focal point and draw attention to it with a bold colour, making your worst feature, your best feature. Left alone, this ceiling would make this room feel cavernous. Here, green highlights the shape of the roof and make room cozy.