If you prefer playing within the game's mechanics, these "exploits" can net you millions of credits:
You can use Cheat Engine to find the memory address for your current balance and change it to any amount. Uplink Money Cheats
While in the game, press F1 to bring up a secret menu that allows you to give your agent money and manage other stats. If you prefer playing within the game's mechanics,
This cheat may not work on all versions of the game, specifically version 1.2. Save Editing & External Tools Save Editing & External Tools I'm the richest
I'm the richest man in the Uplink world... - Uplink: Hacker Elite
Some players use an SQL editor or hex editor to modify save files directly, though this can sometimes trigger anti-cheat measures or corrupt the save. Efficient In-Game Methods (Non-Cheat)
Instead of many small transfers, you can pool cash from multiple accounts (A to B to C) before making one final transfer to your account. This minimizes the number of connections you need to scrub, reducing the risk of a trace.