Remember when you had to click on an application to make it active, and hit refresh in order to find out if anything new had happened? It’s been a long while now, since most desktop programs can run in the background and notify you when something requires your attention. The iPhone approximates that same functionality via the newly introduced push notification features, though apps aren’t actually running in the background, so special support is required from app developers to enable it.

As far as I’m concerned, push has already been a game-changer. My iPhone is now my dedicated IM client, lets me monitor any and all Blue Jays games no matter where I am, and keeps me on-task with my to-do list. But that’s not all. Thanks to a new app called Prowl ($2.99, iTunes link), my iPhone can keep me abreast of pretty much anything, via my Mac and a useful app many will already be familiar with, Growl.

Growl, in case you aren’t aware, is an open notification platform for OS X that supports a wide variety of applications. Basically, it alerts you via an on-screen pop-up and/or sound when one of its supported applications receives a message, finishes a task, and so on. So, for example, using a Mail plugin, I receive a Growl notification whenever I get an email, or when I’m mentioned or receive a DM on Twitter via Tweetie’s built-in Growl support. It’s a very handy tool to have, especially if you keep your dock hidden, as I do, or if you’re working with many different applications on multiple screens.

Now you can receive Growl notifications on your iPhone, too, in the form of push notifications, thanks to Prowl. I can’t even begin to explain how useful this could potentially be, depending on your usage. Already, I have it set up to notify me of new mail (which works better than Apple’s wn push mail, in my opinion, because it allows me to see the sender and some content of the received message), let me know when I receive new @ replies and DMs via Twitter (which I can then check out in Tweetie), and alert me whenever Transmission finishes downloading or seeding a torrent file.

Not only can Prowl alert you of whatever Growl can, but it can also receive custom alerts sent from a web interface. When you set up Prowl, you sign up for an account that’s necessary for syncing Growl on your computer with Prowl on your iPhone. Using that same login, you can go to the Prowl web site and send yourself messages. Any applicable content in that message will be automatically hot-linked, like emails and phone numbers. Very handy for sending a contact number to yourself for future reference.

Prowl is potentially the most effective application of push I’ve yet seen on the iPhone platform, especially if you’re already using Growl (which you should be). The best part is that it’s limited only by Growl itself, which is infinitely expandable, so long as developers keep supporting it. Probably the best $3 I’ve ever spent in the App Store.

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I had to fight a little reluctance, and remove my Transmission icon from my dock so it wouldn’t see my betrayal, but I managed to download and install the new beta. I have to admit, µTorrent’s icon is very appealing. Score one for the newcomer. It also opened very quickly, revealing a minimal, Mac-friendly, attractive user interface. So this is what temptation feels like.

With the proper ports forwarded in my firewall, and running one after the other, not simultaneously, I found download speeds to be roughly the same in both applications on my test file, a (legally) free audio book of Mark Twain’s Tom Sawyer. Both feature individual file prioritization, speed limits, peer information, and ratio monitoring and automatic stopping of seeding at customizable ratios. After I performed my brief test, I had to ask myself: would µTorrent unseat Transmission as my go-to torrent client?

There are a few reasons why it won’t. First, I really like Transmission’s automatic resizing of the application window to fit active torrents. It may be a minor feature, but I’m nuts for it. Can’t go back. Second, the Transmission icon can be badged with upload and download rate, while µTorrent’s cannot. That at-a-glance access to rate information saves me a lot of time in obsessive application window switching. Finally, Transmission supports remote control, groups, speed limit scheduling, and has an auto-add function for a folder you specify. That’s a lot of “finalies”, I realize, but I don’t want to overdo it with the feature listing. It’s probably the product of having been an actively developed app for far longer than µTorrent has, but Transmission still wins nonetheless.  Recent Windows-switchers will have a familiar face to greet them when they cross over though, and that’s always a good thing.

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For the same $1.99 price iTunes charges you for a typical 30-minute or 60-minute television episode, Apple is offering some of the greatest games in baseball history, be they 2 1/2 hours or 3 1/2 hours long. While full-length feature films of the same duration can go for $9.99 or $12.99, less than 2 bucks can bring the game to your computer, or in concert with AppleTV, to your big screen.

Though a diehard A’s fan still suffering scars from the 1988 World Series loss to the Dodgers, I put down $1.99 to relive Kirk Gibson’s walk-off home run against Dennis Eckersley. I paid $1.99 to see the great Nolan Ryan pitch the last of his record 7 no-hitters. And I paid $1.99 to see the Curse of Babe Ruth extended one more year as Aaron Boone sent the Yankees to the World Series, ending the Red Sox season in gut-wrenching fashion.

See thumbnails from the games below. Click any of the three to enlarge.

MLB.com’s Baseball’s Best offers 11 different classic games for download, dating all the way back to 1952′s World Series which saw the Yankees prevail over the Brooklyn Dodgers.

Prefer more recent games? MLB.com also offers the American League Game of the Week and National League Game of the Week. Each game is the same $1.99, and you could subscribe to the entire season for $19.99.

With baseball offering more than a century’s worth of highlights and thrills, there’s no doubt this is just the tip of the iceberg, and iTunes has made it incredibly easy to take the ballgame home. You’re responsible for the popcorn, peanuts and Cracker Jacks, at additional charge.

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