In mid of 2011, I came across a package offered by Celcom dealer in conjunction with a supermarket. You just need to be main line for non-Celcom mobile service, be it prepaid or post paid, and you need to be the member of the supermarket as well, membership is free of charge.
After considering for some time, I asked my family to convert to Celcom. The contract is valid for 24 months and the first month each line is charged for RM10 stamp duty with monthly commitment of RM2. This package is actually the same as Celcom biz Voice Plan P98 which you need to pay RM98 monthly if you walk in to Celcom centre.
It has been 5 months since I switch to Celcom and my monthly average phone bill has dropped 50% to RM10 as monthly fee is much lower and I can enjoy 3000 minutes of free calls with people under the same corporate. Although the line is not as clear and good as Maxis, it is still a very good deal.
I heard that Celcom dealer is doing this promotion for some MNCs like Intel, Sony and Dell too. If you come across Celcom roadshow, you may approach and enquire about this great package.