Well, I deal with thousands of terabytes regularly, so I don't need my console to have much hard drive space to make me think it's usable.  Which is a good thing, because my 360 only has a 20GB drive.

1000's of TB?  Are you from the future?

 In my job, we record TB's of data every day we do testing. I don't personally have anything to do with it, but I have seen 8-10 TB drives be shipped out for a test we were about to do. When they came back, I'm sure they are full. And that is only for 1 set of tests for 1 project. There are lots of other projects that require more information.

Also, If he works in IT, I'm sure our IT department backs up at least a couple TB every day. 800 employees, with 50GB backup drives, that get backed up every night, so you have something like 40TB backups every day, plus they have to back up a few more TB for the servers. 

I'm running out of spcae on my Wii, I think I have 70 blocks left, I have 15 games on my Wii, all channels and 8VC games and 2 WW games.

 My laptop has 40GB, and I haven't even used half of it.

Although he eems to have disappeared, I may as well respond to the OP.
512MB is easily enough for nearly all Wii owners, If you are planning on downloading all the largest Wii ware games then you might fill it, but that is unlikely, and it is easy to swap and change between SD and main memory.

If you are not getting any VC or Wii Ware then you won't even fill half of it as most games use only 2 or 3 blocks out of 2000, the are exceptions like SSBB and Endless Ocean (150ish and 87 respectively I think) , the internet channel takes up the most space (about 1/10th of the whole memory I think) wheras N64 games take between 1/50th and 1/30th, and any 2D games are minimal.

I can't get Wii Ware yet so I don't know how much space it takes, I think the maximum is 40GB which is about 1/12th.

 Hmmm.  I personally have 2 WiiWare games (Including FFCC:MLaaK), all but 3 channels, 25 games, and 25 Virtual Console games and I have 110 blocks left.

 It depends on the games and channels you have. SSBB takes ~128, Elebits ~110, Nintendo channel ~200. Internet channel ~80. Metriod channel ~70, Mario Kart Wii ~70. So that is ~650 blocks just on 6 items.

I have 22 VC games and save files for those VC and 12 additional wii games (including smash's huge save file) plus every channel (internet,evc, news, weather, cmo) ... and I haven't run out of space....

but I'm close to running out...  though since I don't need to play all the VC games at one time.... I think i'll tuck the lesser played ones away onto the SD card.

I'm content with the internal storage solution.... it's cheap. 2GB sd card cost me 9 bucks on tigerdirect. 

 Actually it takes up way more than that. In the channels menu I think it says 250+ blocks, wheras in the memory management bit it must depend on your favourites/cookies because mine says 50 blocks. So in total it uses 300+ blocks

Ah hang on I will check it properly.

Ok here is my memory usage.

 heh, I forgot about the actual channel