Shield to interface with relays

Hi people!

I'm searching for a shield (or a separate board) I can use to drive a set of relays' coils with the output pins of the Arduino.

I've got these relay boards that are really nice; they have the electronics (simple transistor/diode circuit) to drive the coils of 8 relays (230V, 10A), so I can just connect the pins to the board and go.

What I'd like to find is a shield or board that takes the role of that amplifier circuit (for each pin), so that I can use external, heterogeneos relays (more powerful or less powerful).

Any sugestions?

Many thanks!

Óscar