Funny thread

My full time job involves computer repair and sales. My second to-the-side job involves custom build PCs for home and business users.
For desktops you're always going to be better off getting a custom built PC or building your own. It's the only way you can be assured you'll get the quality and expandability you want. The only bummer is that Windows 7 (or 8) costs $100 per copy. If you can get by with Linux (Ubuntu, Elementary OS, Linux Mint, or Fedora would be my recommendations - the first three are Debian-based with Fedora is RHEL-based), that's a great way to save.
For laptops, the brands to really avoid are Acer/Gateway/eMachines (all the same company) as well as HP/Compaq and Toshiba.
For laptops you're going to be best off with Asus, Lenovo, Dell, or MSI, in no particular order. My current laptop is an Asus and my previous laptop was a Lenovo. There's no easy and/or cost effective way to build your own custom laptop so you're going to be better off choosing one of those brands.
Of course, you could get a Mac, but Apple's OS sucks (in my opinion, I grew up on a Mac and switched to Windows a while ago and never looked back)... and their hardware, while being similar to Asus and Lenovo in quality, is usually very overpriced. The only place their higher end laptops stand out are the displays. They use really nice, high resolution panels. But my currently laptop, Asus Q501LA from Best Buy (yeah, yeah, don't laugh, still the best place to buy a laptop if you know what you're doing and don't listen to their salespeople), has a great IPS 1920x1080 15.6" FHD display. Oh, and did I mention, Apple products are overpriced??
If you do want a Mac, get a Mac Mini and a good quality IPS display from a reputable brand like Samsung, LG, or Dell (in no particular order)...
If you custom build your own Desktop PC here are some brands I would recommend:
CPUs: AMD is great for HTPC's but for everything else an Intel 3rd or 4th Gen Core i-series CPU is going to be the best.
Motherboards: All mobo makes have some good and not-so-good boards. Personally I try to use MSI, Gigabyte, ASRock, and ASUS whenever possible (in that order). Avoid Foxconn branded, ECS/Elitegroup, PCChips, and/or Biostar motherboards.
Hard Drives: WD all the way. Best disks right now are WD10EZEX and WD1003FZEX. AVOID the older WD Black drives like WD1002FAEX, they're hot, slow, noisy, and power hungry. 1TB is the best bang for buck in disks right now especially those two aforementioned models. If you can afford an SSD go for Samsung or Intel, or go home.
Disc drives: LiteOn iHAS124-04 is what I've used in absolutely every PC build up until now. 0 Failures or DOA drives. However they now have a new revision that's problematic so unless you get old stock don't use this model anymore. Sad

Power supplies: if you can spend more go for a Seasonic, preferably an 80Plus Gold or Platinum unit. Most people go overkill on wattage - it's pointless to get a 1000W power supply for a single-GPU system. Yes, even with a GTX Titan or Radeon R9 290X. On he more budget end, FSP (also known as SPI) makes some decent units. HEC's Cougar brand has recently made some decent units as well. In Win is another good budget brand. Antec, Corsair, and Cooler Master have quality control problems and are overhyped and overpriced.
RAM: Mushkin, G.Skill, Kingston, or Crucial. Avoid Corsair.
Cases: I personally prefer Silverstone's designs, but this is mostly opinion. Fractal Design makes some sweet stuff too. Again, I find Antec and Cooler Master overpriced and overhyped in this category.
Graphics: Intel HD onboard graphics are making great headways, but still can't compete with dedicated graphics from AMD or nVidia. Both companies make some great cards and some cards that are bad buys. For any computing like Folding@Home or Bitcoin mining get an AMD GPU. For gaming, get an nVidia GeForce GTX series card, or an AMD Radeon R9 290 or 290X (the only AMD GPUs that don't suck, IMO)... Make sure to get a card with a wide memory bus - this is usually more important than video memory amount. 256-bit 1GB is better than 128-bit 2GB. Unless you do multi-monitor gaming 1 or 2GB is usually sufficient.
That's all I have to say for now. I should really get back to work

Hope I helped somebody! Here are the specs on my main desktop:
-Intel i7-4770K CPU
-MSI Z87M-G43 Motherboard
-16GB (2x8GB) DDR3-1600 Mushkin Blackline Enhanced RAM
-1TB WD Black HDD
-In Win 800W Power Supply (overkill but I got a good deal LOL)
-Silverstone PS07B Case
-Geforce GTX670 2GB Graphics
-LiteOn iHAS124-04 DVDRW
-3x 23" Samsung 1080P LCD monitors