Man, grow your own. Man.

Man. As we seem to be having a little bit of a Spring tease here in the Bay Area, it's natural that one's thoughts gravitate towards outdoors activities. For the lazier of us, "activity" can often mean "gardening". And, in the land of the beer nerd, that can only mean one thing. If you're between the 35º and 55º latitude and have about 20' of vertical outdoor sunny space, you might consider growing your own little hop harvest this summer.
Hop rhizomes - root cuttings from female plants related to the mother variety, be it Cascade or Saaz or Fuggles - are usually available from hop sellers and homebrew supply shops in mid- to late March. Whether you plan on brewing with the flowers or not, hop bines make for beautiful ornamental summer plants similar in appearance and growth pattern to grapevines. Unlike grapes, however, hop bines don't last through the winter. Rather, they die down to the crown, just at the soil's surface, and appear mostly dormant until spring while they form winding root systems called "crowns", from which new shoots appear the following season (meaning, don't be surprised when next year you find hop shoots coming up dozens of feet away from where you originally planted them).
As tempting as it may be to use your homegrown hops for all your brewing needs, there are two things worth taking into consideration. For one, the alpha acid levels in your hops are going to be a mystery unless you decide to pay a chemist to do analyses on samples of your crop. Since most people aren't likely to send their strobiles to the lab, you're probably better off growing aroma and finishing varieties instead. Since the acid utilization of late-kettle or dry-hopped additions is so low, all that matters is that your hops are prepared to deliver the stinky goods. Which brings me to the second concern: drying your hops. Considering that a healthy hop plant will produce up to 2 lbs of cones in its first year, you'll want to pay close attention to the drying and storing of your preciously bitter buddies, lest you want to impart nasty grassy (read hay) notes to the sweat of your labor. Or, you can just wait until the hops look about ready to pick, fire up the kettle, and toss them in fresh off the bine. Green hops can lean towards the grassy side, but in something like an Imperial Pilsner or saison may be just the aroma you want.
Retailers usually have good instructions for how to maximize your hop harvest, but if you want more in-depth information, this book covers the subject quite well. Even if you don't end up brewing with them, I guarantee you'll enjoy picking them off the bine and rubbing them between your hands to release the lupulin oils. Yummy!