One little known new feature of Maemo5 PR1.2 is the support for custom smilies in Conversations (<bragging>which I implemented</bragging>).
I have made a smiley theme based on Tango icons, but it’s not yet in the repositories. Here’s what it looks like:

Tango smilies
You can install it by downloading this file: conversations-tango-smilies_0.1_all.deb, and copying it over to your N900.
Then open an X-Terminal, become root and do:
cd /home/user/MyDocs
dpkg -i conversations-tango-smilies_0.1_all.deb
Once it’s finished, switch to Conversation, go to Settings, and you will have a new button, called Smileys theme. You can select your newly installed Tango theme.
Note: the theme will not work with SMSs and Skype chats. All the other accounts, and SMSs, will use the new theme.
After setting the new theme, go to an IM conversation and see if the new icons are in the smiley picker. If not, a reboot should do.
Enjoy!
Tweakr has been finally promoted to Maemo Extras, check it out at http://maemo.org/downloads/product/Maemo5/tweakr/.
You can now easily install it from the App. manager. I’ll write up a new tutorial someday soon.
Hi. I have released tweakr 0.0.16, which you should be able to install from Maemo Testing in a matter of minutes. A couple of bugs fixed and the Silent profile hardcoded is what’s new. Update!
Hi, a quick update on Tweakr: it has now been promoted to extras-testing, since the reboot loop bug (thanks, hildon-home!) has been fixed.
Also a new feature present: the Profile button in the Status Menu gets replaced by Tweakr’s own button (which looks identical), so that you won’t have get your Status Menu too crowded.
A new feature in Tweakr allows you to extend the sound Profiles to more than just General and Silent.
Tweakr introduces the concept of Profile preset. Presets are Profile settings which can be saved, deleted and assigned to the General profile. This allows you to practically use as many profiles as you want on the N900.
The normal use-case is to first tune the General profile for the new preset you want to save, then open Tweakr and choose the Save current General profile to new preset button. This will allow you to save the settings of the General profile with a new name.

After that, you will find a new button in your Status Menu, as shown in the following screenshot:

You can now select whatever preset you have created before, and its settings will be applied to the General profile.

If you’re not using Tweakr yet, go get it from its download page!
I have been working on a little utility package for Maemo 5, called Tweakr. It’s a Settings applet that lets you tweak little known settings that could otherwise be changed only by editing configuration files by hand.
It has a plugin architecture, so you could write your own plugin too. The ones I have so far are Desktop and Hardware keys.
Desktop
This plugin allows you to edit the labels of the bookmark shortcuts you have on your desktop.
Hardware keys
You can configure the behavior of the Power Key, and whether uncovering the camera lens unlocks the device.
More plugins and feature coming soon!
Here’s some screenshots:

