Pidgin is a popular cross-platform IM that enables you to connect to multiple instant messaging services simultaneously without any obstruction.

For Ubuntu and derivatives/Debian systems

$ sudo apt-get install libpurple-dev libjson-glib-dev cmake gcc
$ git clone git://github.com/EionRobb/skype4pidgin.git
$ cd skype4pidgin/skypeweb
$ mkdir build
$ cd build
$ cmake ..
$ cpack

then install:

$ sudo dpkg -i skypeweb-1.1.0-Linux.deb