Because it's über cool: wiki Mantis
Surprisingly there's not much choice for .eu citizens :-( I'll probably order chinese (Tenodera aridifolia) ones on ebay, then get some native (Mantis religiosa or maybe even Empusa fasciata) when I find it.
So, I ordered and got the chinese ootheca, which hached after a month or two. http://cba.si/pics/20090314_chinese_mantis_day0_1cm.jpeg
After two days they started dropping like flies, and after a week all were dead. I provided them with flies, some moisture, so wtf is missing?
Any live insect should do.
For baby mantises my plan is to grow fruit flies.
Now I have fly colonies, and nothing to eat them. Maybe this should be another project, experimenting with genetics. http://biology.arizona.edu/sciconn/lessons2/Geiger/intro2.htm#ane