These are my favorites in different software categories for Android.
Specific sites:
A list of must-have apps.
Touch Calendar is a calendar application with an interesting concept of zooming in and out of visual calendar surface. Has a nice widget, too. Makes an overview easy and simple by displaying the actual times and titles of events on the calendar surface.
Business Calendar Beta is a nice-looking calendar application. It does only display lines, though, in the month view, instead of actual times and event titles. Has nice week view and agenda screens.
Financisto is nice and quick, simple finance application. I find it faster to transfer transactions from the device manually than use QIF import/export. A fast Android application really helps in that regard.
anMoney (link) has a decent implementation of QIF. It can read Quicken QIF files and restore transaction from a desktop application to the device and vice versa.
Application Launcher: Launcher Pro (link, icons)
Quite a convenient utility is Elixir 2. It allows creating a shortcut tab in notification window. To create a link to Home, select Shortcut, then Elixir, then Home / Default Launcher.
Recent Apps application displays the list of recent applications same as when holding Home button.
Synchronization with Outlook is still not perfect but there are multiple solutions to achieve this goal.
One tool that synchronizes most of the PIM items is CompanionLink. Alternatively, try some of the solutions below.
CSipSimple has a wonderful dialer and integration into all the functions of the phone - dialer and SMS. Can dial SIP addresses. Recommended for its implementation of SIP stack. Can be configured to only receive or make calls, or both.
SipDroid - integrates into standard dialer and has a poor interface of its own.
TruPhone (link)