This app is supposed to perform actions (switching your phone profile between silent/beep/ring or creating a reminder) when a predefined rule is true.
Rules are based on your location, the current time, and calendar keywords, and days of the week.
It's in the Ovi store but they take forever to update new versions... If you need to download it from there, try these links:
Fixed web browser: http://store.ovi.com/content/241275
Nokia mobile browser: http://store.ovi.mobi/content/241275

This is the latest version: (old ones are still on the server if you can guess the filename)
http://www.appcheck.net/storage/prox....3.4_armel.deb

Changelog:
proximus-complete (1.3.5) unstable; urgency=low
* Fix bug that will cause "status check delayed (again) by pending wifi scan" repeated forever

proximus-complete (1.3.4) unstable; urgency=low
* fixed some bugs with timers for rules with time
-- lance colton <lance.colton@gmail.com> Tue, 27 Mar 2012 20:25:33 -0600

proximus-complete (1.3.3) unstable; urgency=low
* Improved rule setting screen

-- lance colton <lance.colton@gmail.com> Thu, 15 Mar 2012 23:03:32 -0600

proximus-complete (1.3.2) unstable; urgency=low
* fixed bug that causes wifi scans to queue endlessly when they fail multiple times

-- lance colton <lance.colton@gmail.com> Wed, 07 Mar 2012 21:29:06 -0700

proximus-complete (1.3.1) unstable; urgency=low
* can monitor charging status and create rules based on this
- if this doesn't work correctly, restart the phone by holding in the power button 10 seconds
- let me know if this happens often, it's a bug with harmattan but I could work around it

-- lance colton <lance.colton@gmail.com> Wed, 29 Feb 2012 19:59:15 -0700
proximus-complete (1.3.0) unstable; urgency=low
* supports running custom commands

-- lance colton <lance.colton@gmail.com> Sun, 26 Feb 2012 21:30:25 -0700

proximus-complete (1.2.9) unstable; urgency=low
* new option to force device into power save mode. will switch back to normal when the rule becomes inactive.
* profile switch is now queued and executing after 3-4 seconds to avoid multiple rules causing several changes in a row

proximus-complete (1.2.8) unstable; urgency=low
* rules can be sorted and will execute in that order
* more bug fixes, optimizations
* can now enter almost any characters in wifi ssid
- wifi ssid is now seperated by commas instead of spaces, make sure to update any existing rules

proximus-complete (1.2.7) unstable; urgency=low
* added scrollbars and improved layout of rule setting screen
* fixed minor bugs

-- lance colton <lance.colton@gmail.com> Tue, 07 Feb 2012 01:45:07 -0700

proximus-complete (1.2.6) unstable; urgency=low
* Days of Week support added
* Inverted color theme by default, menu option to switch. this setting is saved.
* minor changes to code to support inverted theme

-- lance colton <lance.colton@gmail.com> Sat, 04 Feb 2012 18:55:07 -0700

proximus-complete (1.2.5) unstable; urgency=low
* better logging. status screen now shows what the daemon is doing.

-- lance colton <lance.colton@gmail.com> Thu, 02 Feb 2012 01:12:03 -0700

proximus-complete (1.2.4) unstable; urgency=low
* external dbus interface listens for a request to create a heartbeat timer and emits it as a signal

proximus-complete (1.2.3) unstable; urgency=low
* fixed bug that rule with gps location still started gps when gps disabled in settings

-- lance colton <lance.colton@gmail.com> Wed, 18 Jan 2012 14:50:40 -0700
proximus-complete (1.2.2) unstable; urgency=low
* fixed bug blocking blank ssid even when disabled section

-- lance colton <lance.colton@gmail.com> Wed, 18 Jan 2012 13:21:51 -0700

proximus-complete (1.2.1) unstable; urgency=low
* Integrated TumblerDialog to fix pre PR1.1 phones

-- lance colton <lance.colton@gmail.com> Wed, 18 Jan 2012 12:28:04 -0700
proximus-complete (1.2.0) unstable; urgency=low
* added new action, setting "visual reminder". basically will pop up an
alarm event when you are at the predefined location

-- lance colton <lance.colton@gmail.com> Tue, 17 Jan 2012 19:40:02 -0700

proximus-complete (1.1.0) unstable; urgency=low
* added support for wifi network scanning and rules
* also added option to disable other positioning completely
- this should fix increased battery usage

-- lance colton <lance.colton@gmail.com> Sun, 15 Jan 2012 22:28:37 -0700

proximus-complete (1.0.1) unstable; urgency=low
* Fix bug causing time rule activation not to do anything

-- lance colton <lance.colton@gmail.com> Thu, 12 Jan 2012 21:21:28 -0700

proximus-complete (1.0.0) unstable; urgency=low
* Initial Release

-- lance colton <lance.colton@gmail.com> Wed, 28 Dec 2011 02:27:40 -0800

source is here: https://gitorious.org/proximus-qml/complete

Unless nokia fixes this bug, leave the "use gps" thing on, or turn off the nokia positioning methods.

you can create a rule that is only active if the calendar has an event at the same time, like tell it to search for "meeting" and go silent or whatever.

Wow, very nice. I'll try it out. Looks pretty cool.

I'll report back with any problems.

This works as daemon at startup?

yeah it installs two seperate things, one of these is a daemon, the other is the gui. As per Nokia requirements, the daemon can be disabled from the GUI, but it won't work at all then...

Can you add switching between powersave mode ON/OFF/AUTO based on what time is it?
i really want my phone to switch to powersave ON when i'm going to bed, say... 11:00PM or so, and actually i have to do it manually. Thanks

3rd party apps can't adjust the power saving mode because the required aegis token is not allowed by Nokia. Maybe they will allow it or we can find some other way, or just have features that require an aegis free kernel

how is this when compared to alarmed on the n900, when it comes versatility and command execution?

@Creamy Goodness
The app seems to work fine except for the GPS use. I have only one rule defined (for work time to be silent) and have disabled GPS use but it still seems to want to use it anyway.
No other programs are open when it tries to determine position and it only started after installing this. Not sure how I could look into it and determine exactly if it is the culprit and what could be done about it but I thought I'd let you know.
FWIW, I've done a reboot or two and it still does it.

Looks great!
Would It be possible to add detection of wlan access points for rules?
A Nice feature would be the ability to switch background connections on/off.