The close tactics.
I used to make a formation with guardsmen veterans with melta bombs, and two leman russes. I packed them in a box formation while the leman russes soaked they volley of bolt's with there 14 FA! While the veteran's brace themselves for a suicide assault that might end up taking there lives.
I used it to get a jump on land raiders and the vehicles that had a strategic value to the enemy. Once the leman russ "cargo" were in range. The hardy veteran's charge the nuts and bolt's, plant there bombs on the hull and destroy it. Sometimes it's a suicidal assault. The operation might actually... maybe wreck a leman russ. Maybe causing a well hardened team of demo's to.... Die. But usually the russes might be a coin flip on the survival of the tank. But hey! It's a good tactic on poor tactician's or maybe you could beat me with this tactic.

Death from above tactic.
Using a well numbered basilisk arty team. That are well defended by hardy guard's(men). You can fire earthshaker rounds at the squishy space marines with ease! No cover save this time! Sometimes I use this but now I don't. (mostly because of the stupid deep striker's DAMN YOU) but if you make a well placed blob. You might actually kill those deep striker's by number's! Don't worry about them too much. Unless there's enemy arty in the distance. I advice you to stand down.

one bullet only tactic
USE THE VINDI