Searching.
To be specific:
#1: Searching and expecting to find any results older than 5 days
#2: Searching for with an until date more than 7 days ago – this is an option on the Advanced Search page, and has returned a HTTP/404 for at least a year now
#3: Partial matches – I can find this post (for the next 4 days) by searching for Ozzy or fucking, but not fuck
#4: source containing anything with a space. I can search for source:Tweetie but not source:"Twitter for iPhone"
The site fails miserably at it's sole purpose – searching.
