What does Google say? He (or She) has far more information than the sum of all the Arduino users... Try there First and then bring the questions you have after your search here for more 'selective' answers. Your question is open ended and until it is better bound, unanswerable as there are too many variables... including but not limited to "How Big is this thing" which you declined to accurately state.
I Quote:
display with a few 8x8 (or any other size, doesnt really matter) led matrixes.
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Size Does Matter... A Lot... so start looking at what has been done and pick your 'ultimate project first... then come ask how to make it. You'll get much better answers.
Bob