Vinyl cutter / plotter

Standard in the MIT inventory is the Roland CAMM-1 GX-24 wide vinyl cutter, it cuts 60 cms wide. Price around € 2000

If 30 cms wide is sufficient, then the SILHOUETTE CAMEO is great for only € 300
When you replace the knife blade by a pen, it doubles as a plotter .

The Silhouette Studio software is extremely friendly and intuitive
It is free, not open source and will import .dxf files from any 2D package.  Mac + Windows.
A $ 50 software upgrade will also directly import .svg files, saving you the conversion from svg to dxf in inkscape.
It is a fun thing to take to schools, as it also can print stand alone from an SD-card.
A previous version, the SILHOUETTE SD, accepts 20 cm wide, A4, and can be found on sales. The SD (below) uses the same software package. Silhouette recently launched a revamped version of it, the PORTRAIT.

If 30 cms wide is not enough and you need 60 cms, have a look at the CGC Expert 24, which cost about € 600. Windows only though.