Another very interesting plant that I want to recommend that we grow next season is the Egyptian Walking Onion. They are also commonly called tree onions, top onions, or topsetting onions (Allium cepa var. proliferum ).
A field of Walking Onions
Bulblets forming at the tops of the stems
This hardy perennial onion, unlike most other types of alliums, grows bulblets (small bulbs) at the tops of its leaves. These bulblets can be eaten (they're very mild), or they can be planted just like onion sets to produce more walking onions. The term "walking" refers to the fact that if the bulblets are left on the plant, they eventually get big and heavy enough to cause the stems to bend to the point where the bulblets come into contact with the soil, at which point the bulblets take root and start new plants. Thus, these alliums can "walk" their way across your garden (if you let them).
For more on this amazing and alluring allium: