[G4] Mac Mini Questions

[Orlando Mac Geek]

Hello all,  I had a few questions about the Mac mini, thought I might
be able to pick some brains here.

1.  I just upgraded from a Powerbook Titanium 667 to the base Mac
mini.  I Had to sell the laptop before I got the mini, so was not able
to do the whole firewire transfer thing of my data.  What I wound up
doing was using Carbon Copy Cloner to backup and restore to the Mini. 
Once I did that, everything seems to be working great, but I am left
with the battery display by my clock and the airport display there as
well.  Since I have neither battery or airport in the Mini, these are
rather annoying.  Does anyone have any idea how to get rid of them?

2.  I am planning to add some memory to my Mini.  Is it true you void
your warranty if you install the memory yourself?  I am not going to
pay the Apple store more to install the memory then it costs to
actually buy it!

3.  Does anyone know of any good Mac compatible 802.11g USB NICs?

4.  Has anyone out there running the Tiger betas had any experience
with the Mac mini, am curious to know performace wise if the Mini has
the power needed to really run Tiger well.

Thanks in advance,
Orlando Mac Geek