If you want a trial visit the dev's page. October 8th, I believe they posted a link to download a demo version of the app w/ a ten item limitation. Version 5, but not 5.0.1 as far as I know.

Link: http://com.chromedomesoftware.s3.amazonaws.com/Check_Off_5.0_Demo.zip

I would be interested to hear if this really makes much of a difference. I have not tried this product but I have tried the two other products offered by the same company and both deserve outstanding marks, hopefully VMOptimizer can be as useful as iDefrag and iPartition. Apparently VMO uses some of iDefrag's technology.

Alfred as it stands is a very intuitive app launcher and spotlight "front end" so to speak. Without the powerpack it is feature deprived and you would be better off imo sticking with Quicksilver. Even with the powerpack it has a pretty UI all around and can definitely do a lot more but functionality is still rather basic. It's important to remember that this is only version 0.9 and the developers are very active. There will be a developer API and I believe the app will continue to progress at a rapid pace, hopefully. Benefit over Quicksilver is the fact that it uses less resources and is more responsive but then again less powerful. QS is open source and although being developed very actively right now, that could drop off as it is the nature of open source software although QS has a large following. Development of Alfred could come to a stand still one day too though, we have seen many shareware apps abandoned.

QS and Alfred work differently, whatever workflow you prefer then go with that. If you like how the "basic" Alfred looks and functions you will love the power pack features but even then the app has not reached maturity. I love QS but I feel Alfred has a lot of potential if it continues to be developed at this pace. Dev's are responsive and that is a perk of having paid for an app. QS help is readily available as well though, especially now. Really can't say one is better than the other as they are completely different. I like both, I just need Alfred to be a bit more powerful than it currently is even with the power pack so I'm looking forward to later releases.

Try them all, see which you prefer, that is the benefit of having so many options. Just as a note, I have tried Launchbar but do not like it at all. Many love it though so give it a try.

Currently I use Alfred until I run into a situation where I need to pull out Quicksilver to perform more complex tasks. A predicament I am faced with since I want to like Alfred very much and the fact that it is lightweight but it still has a ways to go. Sorry for the rant and hopefully this helps someone.

Free but very basic as Ean said below. Definitely could use a hotkey and much more. I hope to see this develop into something very interesting. Thanks and look forward to future versions.

Hotkeys don't stick... Pretty hard to test an app w/o those features plus has anyone figured out a way to "tab" or move over to the right-panel to fill in all the note details w/o having to leave your keyboard... i.e. no mouse... Thanks, dev, please look at hotkey bug, I am on 10.6.2 mbp late '08. Thanks, I thought this app was dead... good to see an update!

Everybody's tun tap working with 10.6? I get it to "stick" for 1 minute max... It says connected to tun0 but after a couple minutes it no longer works... well it says' it does "connected" but no net stat shows no input or output, websites can't connect etc... Would love if anyone has a clue how I can fix this or if you have ran into the same problem. I don't think it is with viscosity but 10.6?.?.? Thanks.