Another vote for the Swisstool Spirit! Compact, elegant, and lighter than the rest, while still have the strength of a full sized tool. Just note that it doesn't have a pointy, straight edge blade (it has a squared-off, serrated one). It can be had for a little over $45 shipped at Amazon, which is really good considering the quality and compared with others on the market.
If you want something even smaller, check out the Leatherman Juice line (the S2 is the lightest/cheapest and has the most useful combo of tools IMHO) but realize that they aren't nearly as robust due to the skeletonized steel/aluminum frames and lighter build in general.
If you don't mind something bigger/heavier there are many options out there- the Swisstool line (standard, RS, CS, X) and the Leatherman Charge, Surge, and Core are among the toughest.