@mhansen - Great ideas! I will expand on idea 2.
I second mhansen on looking for alternatives to adsense. Depending on your how specific your niche is and maybe it doesn't need to be that specific, but you are probably too small for advertisers to come knocking on your door. However, you might be big enough (or have enough quality traffic) for them to bite on your pitch in terms of advertising and definitely for free products to review.