What genres of apps do you usually get? - Spidra Webster

Laptop for me is usually just for work, so productivity apps. I've got Twitter (duh!) and Dropbox so far. Will get my copy of Office installed soon. - Andrew Trinh from IM

Must-haves for me are Carbon Copy Cloner although you can just use Time Machine, I guess. Reunion for genealogy. 1Password for keeping passwords. Cocktail for automating some OS X maintenance routines. AppShelf has been very useful for helping me track reg #s for software. AppZapper is good for getting rid of all the little bits of an app you're deleting, not just the app itself. Delicious Library for inventory of your books, games, music. OmniGraffle for making flowcharts, etc. - Spidra Webster

Adium if you IM.. - Rodfather from iPhone

And definitely Undercover. I buy and put that on all my Apple hardware. - Spidra Webster

xcode if you code - imabonehead

1Password keeps track of my passwords and registration numbers. I forgot about AppZapper! Delicious Library looks pretty awesome, but I'm wary of having just Mac-only software for my database. I use Trillian for IM since it syncs between multiple devices and looking into Undercover. - Andrew Trinh

I also discovered Albert and that's pretty handy. For those of you that remember QuickSilver, it's like the updated version. - Andrew Trinh

Just upgraded from Audio Hijack to Audio Hijack Pro today and figured I should namecheck that app here. It's useful for recording sound from any source on your computer. - Spidra Webster

1Password, TrashMe, Tinderbox, DEVONthink, Adium, Alfred, Pixelmator, Reeder, TotalFinder... - Akiva

I like TotalFinder and MenuCalendarClock. iStat Menus too. And Evernote. And if you use Mail.app then MsgFiler is a no brainer. - ronin

Woah, nice, ronin. I had never heard of MsgFiler before. I'm all over it. - Akiva

Also Fantastical. And Flux. - Akiva

Quicksilver is essential for me, it makes, it simplifies every thing. Xilisoft video converter, jdownloader or site sucker, Coda, and MacJournal - sofarsoShawn <Pop-Rocks>

Scrivener and MarsEdit based on your needs. - Akiva

Oh, and also some sort of drive maintenance, you may not need to optimize (so they say) but you do need to defragrament & res-assign out of place volumes/files. I use disktoolspro (it works well enough for me), but there's numerous ones out there, I think iDefrag or something, it the way most people go. And one of the StuffIt packages to expand or shrink file sizes - sofarsoShawn <Pop-Rocks>

SecondBar if you have two screens. ShiftIt if you want to zoom and move windows with keys. - Morton Fox

I prefer Psi for IM because it has a built-in character counter. - Morton Fox

TechTool Pro/DiskWarrior. - Mary B, VALUE author

Oo, SecondBar sounds like it'd be real handy for me. Although too bad you can't add a bar for each extra monitor... - ronin

Ooh TotalFinder and Shiftit looks nice. - Rodfather

F.lux (color temperature for indoor lighting — try it for a few hours at night, then turn it off and see what a difference it makes), Adium (IM, IRC), Albert (alternative to Quicksilver, Spotlight, QuickSearchBox, Butler, etc.), BetterTouchTool (lets you assign actions to touchpad gestures, and also lets you resize windows to half/quarter screen), Spark (global hotkeys — I use it for switching to common apps instead of Cmd-Tab), iStat Menus (or MenuMeters) (to monitor cpu, network, especially on my laptop where cpu usage eats up battery). - Amit Patel

Some great suggestions here, thanks everyone! Good to be back on Mac. - Andrew Trinh