Stuff to bring Maps: The Periplus map of Sulawesi is useful. As well as an overall map of Sulawesi and details of regions including South Sulawesi and Tana Toraja, it also has city plans of Makassar, Manado, Rantepao, Palu and Pare Pare. Very handy when you're offline, and more accurate than Google Maps in some instances. You can sometimes buy these maps in airports in Indonesia.
SIM card cutter: If you use an iPhone or other phone with mini-SIM and are thinking of using a local SIM card while you're here (see details below), you might want to buy a cheap SIM card cutter, which should let you cut down a standard sized SIM rather than hunt for one that fits your phone. iPhones are less common in Indonesia due to their cost.
Out and about Cash: Try to carry a bunch of small money (notes/coins less than Rp 50,000) in a convenient pocket whenever you go out, to cover snacks, drinks, becak rides, money for beggars, etc. Many of these micro-businesses aren't able (or are reluctant) to provide change (uang kembali). It's also less embarrassing than fishing around in a wallet full of Rp 100,000s for some small notes.
Local SIM cards and wi-fi modems SIM cards: If you're in Makassar or Sulawesi for more than a few days, you might want to consider getting a local SIM card for your mobile/cell phone. They're cheap. We've been advised that the best network provider for Makassar and Sulawesi in general is Telkomsel. Other providers include Indosat and XL. You can buy SIM cards in lots of places including MTC and Kembang Djawa (see map). Phone credit for calls and text messages is known as pulsa, and you can buy pulsa just about anywhere, including in Alphamart and Indomart stores. Phone credit can be transferred easily between any two people who use the same provider, and this service is offered by lots of people – even in tiny wooden shacks in the back blocks of Sulawesi– for a very modest fee (a few thousand Rp). If you see a sign that says "Jual pulsa" (credit for sale), you're in. You can top up pulsa in increments as small as Rp 10,000. If you want data credit (for mobile internet use), choose a plan that includes it. To buy additional data, you first need to choose a data plan (paket), work out the cost, purchase that amount of pulsa, then use the pulsa to pay for the data credit. You can do this on your phone using a variety of codes that the provider will provide in their regular text messages to you. Alternatively, you can download the provider's smartphone app (e.g. MyTelkomsel) and use that.
Wi-fi modems: If you're here for a while and do not have reliable access to wi-fi, you might consider buying a portable wi-fi modem that you can use to connect multiple devices (laptops, iPads). Our experience was using a Bolt device made by ZTE bought for around Rp 300,000 at MTC. Just add a SIM card (which you first need to activate in your phone), some data credit and you're away.