Those look like flying wire ends that have plastic applied.

You could do the same with existing rigging.

See this:

[link=http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXLGP3&P=ML]Click me![/link]
[link=http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXFV30&P=7]Click me too![/link]

But IMHO an even better option are these:

[link=http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXCLZ1&P=7]Brackets[/link]