The wheels on my city bike are visibly out of true, and the front wheel of the road bike is ever-so-slightly out of true (not enough so it can be felt through the brake lever, but enough so I can see it when I spin the wheel and compare the clearance below the brake pads). The Feedback Truing Station is on sale a few places, and got good reviews:
(That's not the best price I've seen, but it's a good picture.)
A wheel true goes for $20-25 at the local shops, so I could probably justify the price. But if I'm going to get that, I should probably get another chain, and another cassette (I'm on my fourth chain for this cassette - maybe my fifth - and the cassettes are only supposed to last about that many chains; that said, I change my chains more frequently than most, about every 1200 miles... but the cassette is cheap; I can use any 10-speed Shimano/SRAM-compatible 10-speed, as long as the big gear isn't bigger than 28), and another set of cables ('cause they don't eat and they don't rot, and I'm gonna re-cable next winter anyway), and another bottom-bracket cable guide (it's a $2 part, so I change it every time I re-cable), and the original about-$60 order has grown to about $190.
(Sigh.) I don't know if I really want the parts, or if I just feel like spendin' some money.