A great traditional aussy saying. When used in a sentence it refers to how completely and utterly useless something is (as would be tits on a bull)
1. Every time I try to use the fucking phone for calls/sms or internet I get cut off. This phone provider is as useless as tits on a bull. Fucking cunts
2. I saw Shelley walking to the beach today, she was out sunbathing and I requested intercourse, she said she would prefer not to as she is married. That stupid bitch is as good as tits on a bull