Here is an interesting alternative to the $360 MB ball joint press. Looks like an arbor press is required, though.

http://cgi.ebay.com/ebaymotors/MERCEDES-BENZ-TOOLS-BALL-JOINT-INSTALLER-TOOL-1849_W0QQcmdZViewItemQQcategoryZ43996QQihZ007QQitemZ170050179393QQrdZ1QQsspagenameZWDVW