Check out GistBox. It supports searching, editing and labels. Here’s a screenshot:
There’s also a demo video at: http://www.youtube.com/watch?v=VLgyY6lqpsQ
GistBox Clipper (a Chrome extension) also provides the ability to save <pre> tags and arbitrary text on any web page.
Edit:
Unfortunately, GistBox is becoming Cacher cacher.io – the free plan will only include: 15 private snippets, 3 private labels, unlimited public snippets. If you plan on having many private gists then you will need to but (sic) a paid plan. – Bartek Skwira