This is a modified keymap for X11 which I prefer to use on my systems.

It's a US-based layout with some special characters available on the
<Alt>-key on the right side of the space bar. I call it RAlt in this
document. It may be labeled AltGr on some keyboards.

Most charachter are available by holding <RAlt> while typing another
key. E.g. <RAlt>+<a> will give you the german umlaut ä.

Deadkey-combinations are available too for creating accented
characters: Hold <RAlt> and type <,>. Now release <RAlt> and type
the char you want to get accented. 

Overview:
 1) German umlauts, ß and Euro-sign:
	RAlt + A, O, U  ==>  Ä, Ö, Ü
	RAlt + s        ==>  ß
	RAlt + e        ==>  €

 2) Some technical stuff:
	RAlt + m        ==>  µ
	RAlt + 1, 2, 3  ==>  ¹, ², ³
	RAlt + 

 3) Dead keys for creating accented chars:
	RAlt + , + ...	==>  ¸, ç, ȩ, ţ, ḑ, ...
	RAlt + . + ...  ==>  ˙, ȧ, ė, ṫ, ḋ, ...
	RAlt + ` + ...  ==>  à, è, ì, ò, ù, ...
	RAlt + ' + ...  ==>  á, é, í, ó, ú, ...
	RAlt + ; + ...  ==>  ą, ę, į, ǫ, ų, ...
	

To use this keymap, simply concatenate the file 'us.dev-de'
to '/usr/share/X11/xkb/symbols/us' using the 'cat' command:

 # cd /usr/share/X11/xkb/symbols
 # cat ~/your-git-stuff/Keymap/us.dev-de >> us


Activate the keymap with setxkbmap:
 
 $ setxkbmap us dev-de

Please keep a copy of your original files before you replace
or modify anything!