Usefulness of a wireless repeater/ range booster of some kind

I'm wondering about the usefulness of something to boost a router's range. Could one provide noticeable improvement if well-placed? The consoles and other computers are fairly far away from the main computer with the router, so I'm looking for a way to make the connection with these better.

We need distances and obstructions, as well as current equipment.

Yes, a repeater would do you well. The trouble is trying to get routers that cooperate together in some sort of distribution chain.

Upgrading to higher-gain omni-directional antennas and cards that have increased output power to increase range has some mediocre results for the expense; however, these could be good options if you already have a weak signal to work with.